WO2022165270A1 - Devices, systems, and methods for detecting peritonitis - Google Patents

Abstract

Devices, systems, and methods are provided that may facilitate detecting peritonitis before subject awareness, e.g., for those subjects who are using peritoneal dialysis (PD) in order to treat the infection earlier, which may reduce acute hospitalization costs and/or prevent scarring of the peritoneum to improve PD longevity.

Description

DEVICES, SYSTEMS, AND METHODS FOR DETECTING PERITONITIS

RELATED APPLICATION DATA

The present application claims benefit of co-pending U.S. provisional applications Serial Nos. 63/143,747, filed January 29, 2021, and 63/189,633, filed May 17, 2021, the entire disclosures of which are expressly incorporated by reference herein.

TECHNICAL FIELD

The present application relates to devices, systems, and methods for screening or detecting infections, e.g., peritonitis in peritoneal dialysis patients.

BACKGROUND

Over 26,500 patients in the U.S. alone, and 195,000 patients worldwide, use peritoneal dialysis (“PD”) to treat their end-stage renal disease (“ESRD”). Dialysis is the removal of waste products — that the kidneys would usually filter from the blood — using a dialyzer, and PD is a method of dialysis that uses the patient’s own peritoneum to filter out these impurities comfortably within the patient’s own home. This alternative to hemodialysis (“HD”) frees patients from costly dialysis center visits multiple times a week while also providing a more continuous and healthier filtration process for the body.

While PD is rising in popularity across the United States due to these key benefits, the treatment also owns its fair share of drawbacks. One of the most notable problems regarding PD is the potential for infection of the peritoneum, known as peritonitis. This infection, which affects nearly 13% of PD users annually, is not only potentially deadly, but it can also lead to long-term scarring of the peritoneum if the infection is not treated quickly. If severe enough, this peritoneal scarring will prevent the peritoneum from acting as an efficient exchange barrier, thus rendering PD impossible and limiting the patient to weekly HD facility visits. PD can be utilized for up to ten years, but on average, it is only used for two to three years before patients switch to HD due to repeated episodes of infection. While HD demonstrates comparable five and ten-year survival rates, the quality of life in patients undergoing PD has been shown to be significantly higher. PD also saves costs overall, when compared to HD. The patient pays less since they pay upfront for an at- home PD set-up, as opposed to the many HD visit costs HD patients spend. Additionally, insurance companies would save by avoiding the large costs of hospitalization for patients who are infected and diagnosed too late — a value calculated to be $100 million per year, or $3800 per PD patient per year. Thus, it is in the patient’s best interest to remain on PD for as long as possible.

Currently, the only preventative measures for peritonitis are standard healthcare sanitary handling practices, the responsibility falling heavily on the patient who must closely adhere to such standards in order to mitigate their own risk. Following the discovery of the infection after four to ten days from infection symptoms, patients will usually visit their primary care physician where, after a forty eight hour testing protocol, they can then be treated for the infection. This extended amount of time to determine if the patient has developed peritonitis is what ultimately leads to the peritoneal scarring.

Accordingly, devices, systems, and methods for detecting peritonitis, e.g., before patient awareness, would be useful.

SUMMARY

The present application is directed to devices, systems, and methods for screening or detecting infections, e.g., peritonitis in peritoneal dialysis patients. For example, the devices, systems, and methods may detect the presence and/or quantity of white blood cells and/or other pathogens in effluent fluid. Optionally, the devices, systems, and methods herein may facilitate detecting peritonitis before patient awareness, e.g., for those patients who are using peritoneal dialysis (PD), in order to treat the infection earlier, which may reduce acute hospitalization costs and/or prevent scarring of the peritoneum to improve PD longevity.

In the United States, over 26,500 PD patients are at risk for developing peritonitis, or an infection of the peritoneum. Peritonitis causes scarring and prevents the peritoneum from serving as an efficient exchange barrier during PD. Patients then have to switch from the gentler and more convenient method of PD to hemodialysis (HD). The current standard of care for detecting peritonitis involves the patient first self-reporting their symptoms and then sending in their dialysis waste for a white blood cell (WBC) test and bacterial culture which can take up to fourteen days, putting the patient at risk for developing infection complications and leading to large hospitalization costs. Patient compliance and long test turnaround time significantly contribute to the number of PD patients who develop peritoneal scarring. We aim to develop a way to detect peritonitis before patient awareness for those who are using PD in order to treat the infection earlier, thus reducing acute hospitalization costs and preventing scarring of the peritoneum to improve PD longevity.

The devices, systems, and methods herein, generally referred to herein as “OpticLine,” may facilitate screening or detecting peritonitis, e.g., by analyzing the optical density or number of WBCs in dialysis waste to gauge for infection occurrence, e.g., via spectrophotometry or microscopy to detect a significant difference in optical absorption or number between normal and infected dialysis waste samples. The devices may be a handsfree device that only needs a one-time setup and may attach to the drain line of current PD systems to allow for real-time infection detection during a PD session.

In accordance with one example, a device is provided for screening or detecting peritonitis in a subject undergoing peritoneal dialysis using a drain line to drain fluid from the subject’s peritoneal cavity, the device including a housing including a cavity for receiving a component of the drain line; a camera mounted to the housing adjacent the cavity for acquiring images of fluid passing through the component; a processor coupled to the camera for analyzing the images to detect white blood cells in fluid passing through the component; and an output device for providing an output related to the presence of white blood cells in the fluid.

In accordance with another example, a device is provided for detecting peritonitis of a subject undergoing peritoneal dialysis using a drain line to drain fluid from the subject’s peritoneal cavity, the device including a housing including a cavity for receiving a portion of tubing of the drain line; a camera mounted to the housing adjacent the cavity for acquiring images of fluid passing through the tubing; a processor coupled to the camera for analyzing the images to detect white blood cells in fluid passing through the tubing; and an output device for providing an output related to the presence of white blood cells in the fluid.

In accordance with still another example, a system is provided for detecting peritonitis of a subject undergoing peritoneal dialysis that includes a chamber member comprising first and second ends connectable to a drain line extending from a subject’s peritoneal cavity and opposing walls enclosing an interior through which fluid flows when the first and second ends are connected to the drain line; a detector device comprising a housing including a cavity for receiving the chamber member and a detector configured to detect white blood cells in fluid passing through the interior when the chamber member is received in the cavity; and an output device for providing an output related to the presence of white blood cells in the fluid.

In accordance with yet another example, a method is provided for detecting peritonitis of a subject undergoing peritoneal dialysis using a peritoneal catheter communicating with the subject’s peritoneal cavity, the method including coupling a detector device to a drain line providing a fluid path from the subject’s peritoneal cavity; and activating a detector of the detector device to detect white blood cells in fluid passing through the fluid path, the detector device providing an output related to whether the detector detects white blood cells and/or other pathogens in the fluid.

Other aspects and features of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features and design elements of the drawings are not to-scale. On the contrary, the dimensions of the various features and design elements are arbitrarily expanded or reduced for clarity. Included in the drawings are the following figures.

FIG. 1 is a schematic showing a subject undergoing peritoneal dialysis, showing an example of a system including a detector device coupled to a drain line for a dialysate drain bag for detecting the presence of infection.

FIG. 2 is a schematic showing a method for coupling the detector device of FIG. 1 to a drain line using an observation chamber member that may be coupled in series with the drain line and received in the detector device.

FIGS. 3 A and 3B show examples of a detector device including a microscopy detector (FIG. 3 A) and spectrophotometry detector (FIG. 3B) for detecting the presence, density, and/or other quantity of WBCs in fluid passing through a chamber member.

FIG. 4 shows an example of a chamber member that may be included in the system of FIG. 1.

FIGS. 5A and 5B show an example of a detector device in an open position and a closed position, respectively, that may be included in the system of FIG. 1.

FIG. 6 is a schematic showing exemplary components of a detector device. FIG. 7A is a detail of a detector device showing an exemplary configuration of internal components.

FIG. 7B is a detail of a detector device showing a camera for acquiring images for microscopy.

FIGS. 8A and 8B show a display that may be included on a detector device including exemplary outputs providing information to the subject regarding levels of WBCs in their peritoneal effluent.

FIGS. 9A and 9B show a display of a mobile electronic device including exemplary outputs providing information to the subject regarding levels of WBCs in their peritoneal effluent fluid.

FIG. 10 shows an exemplary algorithm for processing images to detect the presence and/or density of WBCs in effluent fluid and estimating WBC concentration for a screening result.

FIG. 11 shows an exemplary method for a subject to use and interact with a detector device.

FIG. 12 shows an example of image batch analyses that may be performed by a processor of a detector device to detect and/or count WBCs in effluent fluid.

FIG. 13 shows an example of a method for tuning an image batch analysis algorithm, such as that shown in FIG. 12.

FIG. 14 shows an example of a counts processing algorithm for predicting average WBC concentrations in effluent fluid.

FIG. 15 shows an example of the results of training a counts processing algorithm.

FIG. 16 shows exemplary unprocessed and processed images of effluent fluid and associated WBC concentrations.

DETAILED DESCRIPTION

Before the examples are described, it is to be understood that the invention is not limited to particular examples described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range, and each range where either, neither or both limits are included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, some potential and exemplary methods and materials are now described.

It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a compound” includes a plurality of such compounds and reference to “the polymer” includes reference to one or more polymers and equivalents thereof known to those skilled in the art, and so forth.

Certain ranges are presented herein with numerical values being preceded by the term “about.” The term “about” is used herein to provide literal support for the exact number that it precedes, as well as a number that is near to or approximately the number that the term precedes. In determining whether a number is near to or approximately a specifically recited number, the near or approximating unrecited number may be a number which, in the context in which it is presented, provides the substantial equivalent of the specifically recited number.

Turning to the drawings, FIG. 1 shows an example of a system 8 that may be used by a patient, user, or other subject 90 to detect peritonitis and/or other infection based on fluid removed from the subject’s peritoneal cavity 92, e.g., using a peritoneal catheter 94 implanted into the user’s abdomen 96, and a dialysate or peritoneal dialysis line set-up 80. In the example shown, the dialysate line set-up 80 includes a “ Y” tubing 82 including a first end 82a connectable to the peritoneal catheter 94, a second end 82b connectable to a source of fluid, e.g., a bag of dialysis solution 84, and a third end 82c to which a drain line, e.g., tubing 86, may be connected to remove effluent fluid, e.g., into collection bag 88 or other collection location, e.g., a toilet, sink, tub, or other drainage device (not shown). Although FIG. 1 shows the subject 90 undergoing continuous ambulatory peritoneal dialysis (“CAPD”), the system 8 may also be used during continuous cycling peritoneal dialysis (“CCPD”) and/or other treatments.

With additional reference to FIG. 2, the system 8 generally includes a chamber member 10 that may be coupled to the drain line 86, and a detector device 30 that may receive the chamber member 10, e.g., within a cavity 34, to detect and/or measure white blood cells (WBCs) and/or other pathogens within fluid passing through the drain line 86, e.g., using a detector, such as a detector 40 and a light source 42 that may positioned on opposite sides of the chamber member 10, as shown in FIGS. 3A and 3B and described further elsewhere herein. Alternatively, the detector device may include a cavity sized to receive a portion of the drain tubing (not shown), e.g., to detect and/or measure WBCs passing through the captured portion.

Turning to FIG. 4, an exemplary chamber member 10 is shown that may be connected to a drain line 86 (not shown, see, e.g., FIGS. 2 and 3B). Generally, the chamber member 10 includes a housing 12 including first and second ends 14a, 14b connectable to a drain line 86, and a plurality of sidewalls 16a and upper and lower walls 16b, 16c enclosing an interior 18 through which fluid flows when the first and second ends 14a, 14b are connected to the drain line 86. The ends 14a, 14b may include one or more connectors for coupling the chamber member 10 to tubing 86a, 86b of the drain line 86. For example, as shown, the first or inlet end 14a may include a male connector, e.g., a tapered sliding connector, over which tubing 86a may be received, and the second or outlet end 14b may include a female connector, e.g., sized to slidably receive a male connector on tubing 86b. Alternatively, one or both ends 14a, 14b may include male or female and/or other connectors, e.g., threaded connectors, Luer lock fittings, clamps, and the like for providing a detachable fluid-tight seal to the drain line 86 and/or drain bag 88, or the chamber member may include a length of tubing integrally formed or attached to one or both of the ends (not shown) that may be connected to a peritoneal catheter and/or collection bag.

The housing 12 may be formed from substantially rigid, biocompatible material, e.g., metal, plastic, or composite materials, formed, for example, by one or more of molding, casting, machining and the like. The walls 16a- 16c may be formed from the same material or may be formed from different materials that are permanently attached together, e.g., using one or more connectors, bonding with adhesive, fusing, welding, and the like. For example, the upper and lower walls 16b, 16c may be formed from separate material, e.g., glass or plastic, than the sidewalls 16a and the ends 14a, 14b that are attached to the sidewalls 16a, e.g., by one or more connectors, interference fit, bonding with adhesive, fusing, welding, and the like.

At least a portion of one or both of the upper and lower walls 16b, 16c may be transparent in at least a frequency range that allows the detector device 30 to analyze fluid passing through the interior 18 of the chamber member 10, as described elsewhere herein. For example, as shown in FIG. 4, the upper wall 16b may have a planar surface including a transparent region 17b, e.g., a window mounted or otherwise attached to the upper wall 16b having desired dimensions, e.g., to limit an area of fluid within the interior 18 exposed to the detector 40. Alternatively, the entire upper surface 16b may be formed from transparent material, e.g., glass, plastic, and the like. Similarly, the lower wall 16c may have a planar surface including a transparent region or may be entirely transparent (not shown), e.g., to allow light from the light source 42 to pass therethrough to backlight fluid within the interior 18 for the detector 40, as described further elsewhere herein.

In one example, the transparent region(s) may be transparent to light within a broad wavelength range of light or a target narrow wavelength range, as desired. For example, if the light source 42 is a light-emitting diode (LED) that transmits white or other broad frequency light, the transparent region(s) should be transparent at least within that wavelength range but may be transparent in a broader frequency range, e.g., from visible to ultraviolet light. Alternatively, if the light source has a narrow wavelength range, e.g., a LED that transmits a narrow band of ultraviolet (UV) light, e.g., at a peak wavelength of 265 nanometers, the transparent regions may be transparent only within the narrow range, if desired, e.g., to filter ambient or other undesired light.

Optionally, if desired, the chamber member 10 may include one or more valves (not shown) to capture fluid within the interior 18 and/or stop fluid flowing along the drain line 86. For example, a manual valve may be provided in the outlet end 14b to capture fluid, and the user may manually close the valve to capture fluid, whereupon the detector 40 may be activated to identify WBCs in the captured sample. After the sample is taken, the user may open the valve to resume flow of the fluid. Alternatively, the valve(s) may be coupled to a controller within the detector device (not shown), which may automatically close and open the valve(s) to capture samples for detection, e.g., one or more times. Tuming to FIGS. 5A-7, an exemplary detector device 30 is shown that includes a housing 32 including a recess or cavity 34 for receiving the chamber member 10 with the detector 40 and light source 42 positioned adjacent the cavity 34, e.g., on opposite sides of the cavity 34, as shown in FIG. 7A. Consequently, as shown in FIG. 3 A, when the chamber member 10 is received in the cavity 34, the detector 40 and light source 42 may be positioned adjacent the lower and upper sides 16c, 16b, respectively, of the chamber member 10, e.g., to detect WBCs or other target materials in fluid passing through the chamber member 10.

In the example shown, the housing 32 includes first and second housing portions 32a, 32b movable between an open position to accommodate placing the chamber member 10 in the cavity 34, e.g., as shown in FIG. 5 A, and a closed position, where the detector 40 and light source 42 are positioned adjacent the upper and lower walls 16b, 16c of the chamber member 10 for use. For example, as shown, the housing portions 32a, 32b may be connected together by one or more hinges 36, e.g., at ends of the housing portions 32a, 32b opposite the cavity 34. Alternatively, the housing portions may be pivotable about an intermediate location, e.g., such that a user may squeeze first ends of the portions to open the other ends to place the chamber member 10 in the cavity and release the first ends to clamp the chamber member 10 within the cavity. In another alternative, the housing portions 32a, 32b may be otherwise separable entirely to allow access to the cavity 34 but may include cooperating features to seat the housing portions together (not shown). In a further alternative, the housing may be a single piece (not shown) and the chamber member 10 may be slidable or otherwise insertable into the cavity from one side of the housing to position the upper and lower walls 32a, 32b adjacent the detector 40 and light source 42.

The housing portions 32a, 32b may be formed from substantially rigid materials, e.g., formed from one or more panels that enclose the interior of each housing portion. Optionally, the housing portions 32a, 32b may be formed as substantially sealed casings that protect interior components from exposure to external materials. For example, if desired, the detector device 30 may be cleaned, e.g., rinsed, wiped, and the like, after use or if contaminated with effluent fluid, without substantial risk of contaminating or otherwise damaging interior components.

Optionally, the housing 32 and/or chamber member 10 may include one or more features for preventing movement of the chamber member 10 when received in the cavity 34, e.g., after closing the housing portions 32a, 32b to the closed position. For example, as shown, the housing 12 of the chamber member 10 may include or more tabs 13, e.g., extending from the sidewalls 16a as best seen in FIG. 4, that may be received in corresponding slots 35 in the cavity 34, e.g., as best seen in FIG. 7. When the chamber member 10 is placed in the cavity 34, the tabs 13 may be received in respective slots 35, thereby preventing the chamber member 10 from sliding out of the cavity 34 during use. In addition or alternatively, one or more surfaces of the housing 32 adjacent the cavity 34 may include a gasket or other nonslip material, e.g., formed from foam and the like, that may engage the housing 12 of the chamber member 10 to prevent substantial movement when the housing portions 32a, 32b are closed. Alternatively, if the cavity is sized to receive a section of drain tubing, one or more walls of the cavity may include features, e.g., gaskets or other non-slip materials and/or textures, to prevent the detector device 30 from sliding when clamped around the tubing.

In addition or alternatively, the housing 32 of the detector device 30 may include a locking mechanism that may be selectively actuated or automatically engaged to secure the housing portions 32a, 32b in the closed position. For example, magnetic components may be mounted in the housing portions 32a, 32b, e.g., adjacent the cavity 34 or otherwise opposite hinges 36, that may be attracted together to secure the housing portions 32a, 32b together. For example, a bar magnet (not shown) may be mounted below the upper surface of the lower portion 32a and a ferromagnetic element, e.g., a complementary magnet or ferromagnetic metal bar may be mounted at a corresponding location in the lower surface of the upper portion 32b. Thus, as the housing portions 32a, 32b are closed towards one another, the magnetic elements may automatically secure the housing 32 closed, but the housing portions 32a, 32b may be easily opened thereafter simply by overcoming the magnetic force. Alternatively, the hinges may include one or more springs that bias the housing portions 32a, 32b to the closed position. In addition or alternatively, a latch (not shown) may be provided on one of the housing portions 32a, 32b that may be manually or automatically actuated to secure the housing 30 closed, which may be released when desired, e.g., after measuring WBCs in the subject’s peritoneal effluent. Optionally, one or both housing portions 32a, 32b may include a handle (not shown), e.g., to facilitate opening and/or closing and/or otherwise manipulating the detector device 30 during use.

With additional reference to FIG. 6, the detector device 30 may include one or more additional components on or within the housing 32. For example, a processor 44 may be provided within the housing 32, e.g., mounted on a PCB or other substrate 45, that may be operatively coupled to other components. As used herein, the term “processor” may include a single processor or a plurality of general or special-purpose processors that perform various functions of the detector device 30. For example, as shown in FIG. 6, the processor 44 may include a real-time processor 44a and a numeric processor 44b.

The processor 44 may be coupled to the detector 40 and light source 42, e.g., to control activation and/or to process signals from the detector 40, as described elsewhere herein. Optionally, as shown in FIG. 6, the detector device 30 may include additional components, such as memory 50, e.g., for storing data and/or operational instructions, a real-time clock 52, a battery and/or other internal power source (not shown), a connector 54 for coupling to an external power source (not shown), an on/off switch 58, and the like, that may be coupled to the processor 44 and/or other components of the detector device 30.

In addition, the detector device 30 may include an output device, e.g., a LCD or other display 48, mounted on the housing 32 and coupled to the processor 44 for providing an output, e.g., related to data acquired from the detector 40 regarding WBC levels in the fluid. FIGS. 8A and 8B show exemplary screenshots of information that may be displayed on such a display 48, as described further elsewhere herein. For example, FIG. 8A presents an output indicating the subject’s level of WBCs is normal, while FIG. 8B presents an output indicating that high levels of WBCs have been detected. Optionally, the display 48 may present additional information to the subject, e.g., a graphical output representing data acquired by the detector 40 during an individual session.

Alternatively, other output devices may be provided, e.g., in addition to or instead of the display 48. For example, one or more indicator lights 48a (e.g., as shown in FIG. 3B) may be provided on the housing 32 that may be coupled to the processor 44, e.g., which may be activated when the detector 40 detects WBCs in the fluid to provide an indication of infection to the subject. For example, a red or other warning light may be provided, which the processor 44 may activate if high levels of WBCs are detected, and/or a green or other positive light may be provided (not shown), which the processor 44 may activate if normal levels of WBCs are detected.

In addition or alternatively, the detector device 30 may be configured to communicate information to a separate electronic device, e.g., a mobile electronic device, such as a cellphone, tablet, laptop computer, and the like. In this alternative, the detector device 40 may include a communication interface 56 for communicating data from the detector 40 and/or processor 44 to a remote location, e.g., to a mobile electronic device 70, as shown in FIG. 6. In one example, the communication interface may include a connector 49 to which a cable (not shown) may be connected to transfer data from the detector device 30 to the electronic device. In addition or alternatively, a wireless communications interface, e.g., a wireless transmitter and/or receiver (not shown) may be provided, e.g., on the PCB 45, configured to communicate via short-range radiofrequency signals, such as Bluetooth or other protocols. In this alternative, signals from the detector 40 may be analyzed or otherwise processed by the processor 44 before being transmitted or raw data may be transmitted for processing by the electronic device 70.

FIGS. 9A and 9B show an example of a mobile electronic device, e.g., a cellphone 70, including a display 72 for presenting information to the subject and/or allowing the subject to use a software application, e.g., to monitor their PD sessions, as described elsewhere herein. Generally, the electronic device 70 includes one or more processors, memory, a communication interface, and one or more user interfaces, e.g., a display or other output device, and a touch screen, keyboard, mouse, touch pad, and/or other input device. In one example, the electronic device 70 may include a touch screen 72 that may act as a display and as an input device, allowing the user to scroll through menus and/or otherwise use the application, as described elsewhere herein.

With continued reference to FIGS. 6 and 7A, the detector device 30 may also include a sensor 46 coupled to the processor 44 for detecting when fluid is present within a chamber member 10 received in the cavity 34, e.g., before acquiring signals from the detector 40. For example, the sensor 46 may be a thermocouple, thermosensor, or other temperature sensor mounted to the housing 32 adjacent the cavity 34 for sensing temperatures within the chamber member 10.

For example, the processor 44 may receive and process signals from the sensor 46 to determine the temperature within the interior 18 of the chamber member 10, e.g., to confirm that effluent fluid is passing through the chamber member 10 during a PD session since such fluid will be warmer than ambient temperatures, e.g., close to body temperature. When the processor 44 determines that the temperature within the interior 18 meets a desired threshold, e.g., at least thirty five degrees Celsius (35 °C), this may confirm that effluent fluid is present within the interior 18 and the processor 44 may then activate the detector 40 and light source 42 to acquire data to detect and/or measure WBCs, as described further elsewhere herein. If the temperature falls below the threshold, the processor 44 may discontinue acquiring or discard data from the detector 40, e.g., if fluid has stopped flowing through the chamber member 10.

Returning to FIGS. 3A and 3B, an exemplary detector arrangement is shown that may be provided within the detector device 30. As shown in FIG. 3A, the detector 40 includes a camera 40a, e.g., a CCD, CMOS, and/or other image sensor, and a lens 40b optically coupled to the camera 40a. For example, the camera 40a may have a desired resolution, e.g., at least eight megapixels (8 mp), and/or may be capable of acquiring images at a desired rate, e.g., at least thirty frames per second, when activated to detect and/or measure WBCs within effluent fluid.

In one example, the lens 40b may be a spherical lens configured to provide a desired magnification and/or focal length for the camera 40a, e.g., a 2.3 millimeter diameter spherical lens that provides about 140x magnification to allow the camera 40a to acquire detailed images of fluid within the interior 18 of the chamber member 10. In the example shown in FIG. 7B, the detector 40 may be mounted in a recess 34a in a lower surface 34b of the cavity 34, e.g., in the lower housing portion 32b. Optionally, the detector 40 may include one or more filters (not shown) to limit bandwidths of light striking the camera 40a, e.g., to filter ambient or other light bands, if desired.

The light source 42 may be mounted in the upper housing portion 32a above the recess 34 to provide a backlight for the camera 40a, e.g., such that light from the light source 42 may pass through the transparent region(s) of the chamber member 10 received in the recess 34 and fluid therein to the camera 40a, e.g., as shown in FIG. 3A. In one example, the light source 42 may be mounted a desired distance away from the detector 40, e.g., mounted in the upper housing portion 32a about two to three centimeters (2-3 cm) away from the lens 40b, and/or may have a hemispherical shape to enhance ambient lighting and/or focus.

In one example, the light source 42 includes a light emitting diode (LED) configured to emit white or other broadband light, e.g., if the detector 40 is used to acquire images for microscopy. Alternatively, if the detector 40 is a photodiode or other detector used for spectrophotometry, the LED may be configured to emit ultraviolet (UV) light, e.g., at a peak wavelength of 265 nanometers. In this alternative, no filter may be needed as ambient light (e.g., at wavelengths between about four hundred and seven hundred nanometers (400-700 nm)) may not interfere with optical absorbance acquired by the detector 40. In addition, with the detector 40 mounted in a recess 34a, exposure of the detector 40 to ambient light may be limited and/or, optionally, a shroud may be provided to further protect the detector 40 from exposure to ambient light.

The light source 42 may have a fixed intensity when activated. Alternatively, the light source 42 may have variable intensity, which may be controlled by the processor 44, e.g., to facilitate processing images from the detector 40, as described elsewhere herein.

With continued reference to FIGS. 3A and 3B, the camera 40a may be used to acquire a series of images of fluid within the interior 18 of the chamber member 10, which may be processed by the processor 44 using desired image processing methods, such as those described further elsewhere herein. For example, as shown in FIG. 10, when activated, the processor 44 may acquire a sequence of images during a PD session of fluid passing through the chamber member 10 using the detector 40, process the images to count WBCs and/or determine concentrations of WBCs within fluid, and present an output to the subject, as described further elsewhere herein. In one processing method, the processor 44 may use microscopy to acquire and process the images, e.g., to remove undesired artifacts and/or count WBC to determine an average concentration of WBCs. Alternatively, spectrophotometry may be used, e.g., as described elsewhere herein and in the applications incorporated by reference herein.

Generally, as shown in FIGS. 1-3, a subject 90 may use the system 8 to detect WBCs and/or other pathogens during a peritoneal dialysis (PD) session, e.g., by coupling a chamber member 10 to a drain line 86 coupled to their peritoneal catheter 94, and placing the chamber member 10 in the cavity of the detector device 30. For example, tubing 86a may be coupled to the inlet end 14a and to the peritoneal catheter 94 via Y tubing 82, and tubing 86b may be coupled to the outlet end 14b and to a collection bag 88. A bag of dialysis solution 84 may be coupled to the Y tubing 82 and the user may open a valve coupled to an outlet of the bag 84 to deliver the solution into their peritoneal cavity 92 and subsequently drain the solution via the drain line 86.

For example, the solution may be delivered into the subject’s peritoneal cavity 92, where it may dwell for a desired duration, e.g., between about thirty and sixty (30-60) minutes. The fluid may then be flushed from the peritoneal cavity 92 via the drain line, which may take between about five and ten (5-10) minutes. Before draining the fluid, the chamber member 10 may be coupled to the tubing 86 and placed in the cavity 34 of the detector device 30. To place the chamber member 10 in the detector device 30, the housing portions 32a, 32b may be opened, the chamber member 10 positioned in the cavity 34, and then the housing portions 32a, 32b may be closed.

Alternatively, if the detector device 30 is configured to clamp directly onto a portion of the drainage tubing, i.e., without using the chamber member 10, the subject may simply open the housing portions 32a, 32b, position the tubing in the cavity, and then close the housing portions 32a, 32b to capture and secure the detector device 30. In this alternative, the entire drainage tubing may be substantially transparent, i.e., to allow light from the light source 42 to backlight fluid passing through the tubing to the camera 40. Alternatively, if only a portion of the tubing is transparent, the transparent portion may include one or more labels, markers, or identifiers to identify the portion to facilitate the subject clamping the detector device 30 over the transparent portion. Optionally, in this alternative, the tubing and/or detector device may include one or more features that provide confirmation to the subject that the detector device is appropriately positioned. For example, the transparent portion may include one or more conductors (not shown) extending along the transparent portion, and the detector device may include contacts that may contact the conductor(s) when properly positioned, e.g., such that the contacts may close a circuit coupled to the processor, which may confirm that the circuit is closed before acquiring image data. Optionally, the processor may provide a negative indication, e.g., on the display or other indicator to the user when the detector device is improperly positioned so the subject may correct the positioning, whereupon a positive indication may be presented.

With additional reference to FIGS. 10 and 11, an exemplary algorithm is shown that may be used by the detector device 30 to detect and/or measure WBCs. Before draining fluid via the drain line 86, the detector device 30 may be turned on, e.g., using on/off switch 58, whereupon the processor 44 may initialize components of the device 30 in preparation for use. Optionally, at step 110, a menu may be presented on the display 48, e.g., allowing the subject to activate the device 30, e.g., to switch the device 30 from a stand-by mode to an active mode to begin taking and processing images to detect WBCs. For example, if the detector device 30 includes the temperature sensor 46, once active, the processor 44 may begin measuring temperature via the sensor 46 to confirm that effluent fluid has begun flowing through the chamber member 10. In addition or alternatively, the processor 44 may acquire a plurality of initial images from the detector 40 and analyze the images to confirm fluid is flowing through the chamber member 10. For example, if the processor 44 determines that a series of images are substantially the same, the processor 44 may conclude that fluid is not yet flowing, while if there is substantial variability between images, the processor 44 may conclude that fluid is flowing due to the variability.

Once confirmed, the processor 44 may activate the detector 40 to acquire a series of images during the session. The processor 44 may simultaneously activate the light source 42 or, alternatively, the light source 42 may be activated during the stand-by mode. In a further alternative, the detector 40 may also be activated during the stand-by mode but the processor 44 may not begin acquiring and/or processing images from the detector 40 until the sensor 46 (and/or the processor 44 initial image analysis) provides confirmation that fluid is passing through the chamber member 10. Thus, in this alternative, any previously acquired images may simply be discarded.

At step 120, once activated, the processor 44 may acquire a series of images using the detector 40 during the PD session, which may be stored in memory 50. At step 130, the images may be processed by the processor 44, e.g., individually or in batches where multiple images are processed simultaneously, to determine cell counts of WBCs in the images and/or determine a mean or average concentration of WBCs in the fluid based on the images. At step 140, information may be presented to the subject, e.g., related to the presence and/or concentration of WBCs in the effluent fluid from the session.

Upon completing the session, the detector device 30 may be deactivated and/or turned off. For example, the processor 44 may determine based on temperature data from the sensor 46 that fluid is no longer passing through the chamber member 10 and automatically discontinue acquiring images. Alternatively, the processor 44 may be configured to acquire images for a set period of time, e.g., once fluid is initially detected. In a further alternative, the subject may enter a stop command after completing the session, e.g., via the display 48 or other interface, whereupon the processor 44 discontinues acquiring images. In this alternative, any acquired images that are associated with a time in which the sensor 46 does not confirm fluid is flowing through the chamber member 10 may be discarded.

Once the session is complete, the chamber member 10 may be disconnected from the tubing 86a, 86b and removed from the cavity 34 of the detector device 30. The housing portions 32a, 32b may be opened to allow removal of the chamber member 10, e.g., before or after disconnecting the tubing 86a, 86b. The chamber member 10 may be cleaned, e.g., rinsed, soaked, and the like, after the session to allow reuse, or the chamber member 10 may be single-use and simply discarded. The detector device 30 may be stored for the next session and/or may be plugged in to recharge. The other devices from the session, e.g., tubing 82, 86 and/or bags 84, 88 may be discarded or cleaned for reuse, using conventional methods.

With continued reference to FIGS. 10 and 11, exemplary outputs are shown that may be presented on the display 48 of the detector device 30 following a PD session. For example, at 140a, if the processor 44 determines that the average concentration of WBCs is below a target threshold, e.g., between about zero and fifty (0-50) WBCs/mm³, the display 48 may inform the subject that they are healthy, that no follow-up is required, and/or that that subject can follow their normal schedule of subsequent PD sessions. Optionally, as shown in FIG. 11, a graph showing average concentrations from images acquired during the current session may be presented on the display 48, e.g., in addition to a status indicator. At 140b, if the processor 44 determines the average concentration of WBCs falls within an intermediate range, e.g., between about fifty and one hundred (50-100) WBCs/mm³, the display 48 may inform the subject to be cautious and/or to monitor their symptoms. Finally, at 140c, if the processor 44 determines the average concentration exceeds a threshold, e.g., above one hundred (100) WBCs/mm³, the display 10 may inform the subject that they are at risk and/or should contact their health care provider, e.g., for follow-up and/or treatment. Optionally, with authorization of the subject, the detector device 30 may automatically communicate information to a remote location, e.g., to their health care provider, using the communication interface 56. For example, if the subject is determined to be at risk, the processor 44 may communicate concentration and/or other information via a network, such as the Internet or a telephone network, to an electronic device of their health care provider to facilitate follow-up. As shown in FIG. 11, at step 150, the subject or the detector device 40 itself may contact the subject’s doctor, which may result in earlier testing, diagnosis, and/or treatment than if the detector device 30 had not been used to detect early presence of WBCs.

Turning to FIGS. 10-12, an exemplary method for processing images acquired by the detector 40, e.g., at step 130 of FIG. 10, is shown. Optionally, one or more filters and/or preprocessing steps may be performed on the individual images and/or on a plurality of images. For example, the processor 44 may determine optimal brightness levels for the light source 42 to enhance creation of full-contrast images. In one method, the processor 44 may increase intensity of the light source 42 to over-saturate one or more images, then decrease intensity to under-saturate one or more images, and then determine optimal intensity for the light source 42 to provide subsequent high-contrast images. Optionally, the processor 44 may distribute levels across the color spectrum of the camera 40a, e.g., to distribute between red-green-blue (RGB) levels to provide maximum contrast.

Alternatively, the intensity of the light source 42 may be preset during manufacturing of the detector device 30.

Optionally, after initially acquiring images, the processor 44 may compare images to identify static items in the field of view, e.g., dirt on the lens 40b, shadows, and the like, which may then be subtracted from the images during subsequent processing.

In addition or alternatively, the processor 44 may analyze the images to identify and discard “bad” images. For example, extreme perturbation of the fluid passing through the chamber member 10 and/or large quantities of bubbles, e.g., which may occur in particular during initial draining, may be identified and the relevant images discarded.

The resulting high-contrast images may then be analyzed, e.g., to identify objects that correspond to WBCs or other target pathogens. For example, the processor 44 may analyze the images, e.g., using a two-step Hough transform, to find shapes predefined as circles (or other target shapes), which may correspond to WBCs in the images, e.g., such as the representative circles 62 shown in image 60 in FIG. 3B. The resulting number of circles/target shapes may then be counted by the processor 44 and, optionally, may correlate the volume of fluid present in the images with the circles counted to determine a concentration of WBCs. Additionally, the processor 44 may use a linear regression model to estimate WBC concentrations based on WBC counts, e.g., based on pre-training the processor 44 and/or other preset algorithm. The information regarding concentration and/or counts, e.g., including data from individual samples and/or averages, may be presented to the subject, e.g., on display 48, as described elsewhere herein.

During a typical PD session, the processor 44 may acquire images at a set rate, e.g., about thirty (30) frames per second, for a minimum duration, e.g., at least about five (5) minutes during drainage. During a PD session, there may be as many as ten (10) releases of fluid from the peritoneal cavity 92, which may produce as many as nine thousand (9,000) images or more. Due to memory constraints, the processor 44 may not save and/or process all of the images but may save a target sample size, e.g., during times when the sensor 46 and/or the processor 44 provide confirmation of fluid flow.

Turning to FIG. 12, an example of batch analysis is shown that may be performed on images by the processor 44. For example, as shown, at step 210, a plurality of images may be combined or “batched” for subsequent processing together. Optionally, the average of the “pooled” pixels at the same (x, ) location across the batch images may be compared with the pixel at the given (x, ) location within each image in a batch of images, e.g., to identify potential cells for subsequent processing. For example, an original image 220 may be pre-processed at 222, e.g., using one or more of the filters or processes described elsewhere herein, e.g., to remove static artifacts, and the like.

At 224, a bubble mask may be applied, e.g., in which artifacts having a size outside the range of target cells may be filtered from the image. For example, artifacts that exceed a size threshold, e.g., corresponding to bubbles, may be removed or otherwise filtered. At 226, a cell mask may be applied, e.g., to identify circles or other artifacts that correspond to WBCs or other target cells, e.g., based on the artifacts falling within a target size range and identified in the batch analysis process described earlier. At 228, centroids of the identified circles may then be plotted and counted to determine the number of cells identified.

At step 132 shown in FIG. 10, the processor 44 may use a counts processing algorithm, to convert the raw cell counts to a concentration, e.g., based on a linear regression model. For example, FIGS. 14 and 15 show an example of a method (FIG. 14) and results (FIG. 15) for training a linear regression model to predict WBC concentrations based on images provided to the model, as shown in FIG. 14. FIG. 15 shows an example comparing actual concentration to predicted concentrations generated by the model during training. FIG. 16 shows examples of images, e.g., both original images, cell masked images, and images with cell centroids, that may correspond to different concentration ranges of WBCs, e.g., reflecting either concentrations that are baseline (0-10 WBCs/mm³), one hundred (100) WBCs/mm³, and three hundred (300) WBCs/mm³.

It will be appreciated that, if desired, the detector devices herein may include a different detector to identify the presence of WBCs in the fluid passing through the fluid path other than a camera using microscopy. In addition or alternatively, the detector may be configured to identify the presence and/or quantify the amounts of other analytes, e.g., instead of or in combination with WBCs.

In one alternative, the detector device may use spectrophotometry to measure the optical density of the waste fluid to see if WBCs and/or potentially other pathogens are present. For example, as described further in the applications incorporated by reference herein, a detector device may be provided that may be clamped or otherwise secured around a portion of a drain line. The detector device may include any components to the detector devices described above, e.g., including a power source, e.g., a DC battery, a light source, e.g., a LED, a sensor, a processor, a communications interface, e.g., a Wi-Fi unit, memory, and an output device. Optionally, the device may include one or more additional components, e.g., a flow meter, one or more valves, and the like. Optionally, a housing of the detector device may include circular clamps and/or other connectors to help keep the drain line tubing defining the internal fluid path in place, e.g., permanently or if the tube is removable.

In this alternative, the detector device may include a UV LED and a sensor, e.g., a photodiode, that may be positioned on opposite sides of a transparent section of the tubing when the detector device is secured around the tubing. For example, the entire length of tubing for the drain line may be UV-transparent so that the subject can place the detector device at any convenient location. Alternatively, only a segment of the tubing may be UV- transparent, which may be labeled or otherwise identified to ensure the subject secures the detector device to the transparent segment. Thus, UV light from the light source may pass through the transparent section of tubing and the photodiode may acquire optical data from effluent fluid passing through the tubing to detect WBC presence and/or concentration. In one example, the sensor may detect the presence of WBCs based on the presence or absence of light from the light source passing through the fluid path.

Similar to other examples, the detector device may include a processor that may receive data from the sensor to determine whether WBCs are present in the fluid and/or to measure a density or other quantity of WBCs in the fluid. In addition, the processor may activate an output device, e.g., activate an LED, present a message on a display, emit a sound or message on a speaker, and the like, similar to the previous devices. In addition or alternatively, the device may transmit data from the sensor to a remote location, e.g., via a wireless communications interface of the device or a wired connection, which may perform an analysis and/or diagnosis, e.g., to merely detect the presence of WBCs, determine whether the quantity exceeds a threshold, and/or evaluate trends.

Optionally, the detector device may include one or more valves and a controller for selectively closing the valves to capture and stop fluid within the fluid path, whereupon the detector may be activated to identify WBCs in the captured sample. After the sample is taken, the controller may open the valves to resume flow of the fluid.

Alternatively, the device may include a reservoir configured to receive a sample of the fluid from the drain line and the detector may determine the presence of fluid in the sample. For example, when activated, a processor may open a valve to the reservoir to capture a sample, whereupon the valve may be closed. After the sample is analyzed, the processor may open the valve again to release the sample into the fluid path.

In another option, material may be added to the fluid within the detector device to enhance detection and/or analysis. For example, the tubing defining the flow path within the detector device may be coated with a dye or other material that may mix with the fluid passing through the flow path. Alternatively, the detector device may include a reservoir containing such material that may be added to the fluid before the fluid enters the range of the detector.

One of the benefits of the devices and systems herein is that they may allow for an earlier diagnosis of infection compared to the current standard of care, e.g., where the subject self-reports their symptoms, which usually arise between four and ten (4-10) days after an infection has already occurred, and then the physician completes a culture, which can take up to a week. Because of this lengthy turn-around, the subject has increased likelihood of developing infection complications and peritoneal scarring, which can lead to hospitalization and prevent long-term PD usage. Thus, the devices and systems herein may facilitate early detection, e.g., within a few days of infection, reducing risk for peritonitis and scarring and/or decreasing the incidence of hospitalization.

In addition, the devices and methods herein may increase compliance by subjects using PD compared to other methods for self-monitoring. For example, at-home WBC counters or infection kits require the subject set up, collect, and communicate results of such self-administered tests, which they may avoid due to potential messiness and inconvenience using such kits. In contrast, the devices and systems herein may allow subjects to attach the device once during setup, whereupon data collection happens simultaneously with PD drainage.

Further, in describing representative examples, the specification may have presented the method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. While the invention is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the scope of the appended claims.

Claims

- 23 -We claim:

1. A system for detecting peritonitis of a subject undergoing peritoneal dialysis, comprising: a chamber member comprising first and second ends connectable to a drain line extending from a subject’s peritoneal cavity and opposing walls enclosing an interior through which fluid flows when the first and second ends are connected to the drain line; a detector device comprising a housing including a cavity for receiving the chamber member and a detector configured to detect white blood cells in fluid passing through the interior when the chamber member is received in the cavity; and an output device for providing an output related to the presence of white blood cells in the fluid.

2. The system of claim 1, further comprising a light source mounted in the housing adjacent the cavity for providing light to the detector.

3. The system of claim 2, wherein the detector and the light source are provided on opposite sides of the cavity such that light from the light source passes through the opposing walls and fluid within the interior when the chamber member is received in the cavity to the detector.

4. The system of claim 3, wherein the opposing walls comprise transparent regions such that the light from the light source passes through the transparent regions to the detector.

5. The system of claim 1, wherein the housing comprises first and second housing portions movable between an open position to accommodate positioning the chamber member in the cavity and a closed position wherein the detector is positioned adjacent one of the opposing walls of the chamber member.

6. The system of claim 5, wherein the housing comprises one or more features for preventing movement of the chamber member when received in the cavity and the housing portions are in the closed position.

7. The system of claim 5, wherein the housing comprises a locking mechanism for securing the housing portions in the closed position.

8. The system of any one of claims 1-5, further comprising one or more connectors for securing the chamber member in the cavity.

9. The system of claim 5, further comprising a light source mounted in the housing adjacent the cavity for providing light to the detector.

10. The system of claim 9, wherein the detector is provided on the first housing portion and the light source is provided on the second housing portion such that the detector and light source are on opposite sides of the cavity such that light from the light source passes through the opposing walls and fluid within the interior when the chamber member is received in the cavity to the detector.

11. The system of any one of claims 1-5, wherein the opposing walls of the chamber member are substantially planar.

12. The system of claim 11, wherein a first wall of the opposing walls comprises a transparent region that is disposed adjacent the detector when the chamber member is received in the cavity such that the detector can detect white blood cells in the fluid.

13. The system of claim 12, further comprising a light source mounted in the housing adjacent the cavity for providing light to the detector.

14. The system of any one of claims 1-5, wherein the detector comprises a spectrophotometer or a microscopy device.

15. The system of any one of claims 1-5, wherein the detector comprises a camera coupled to a processor, the processor configured to analyze images acquired by the camera to detect white blood cells in the fluid.

16. The system of claim 15, wherein the processor is configured to determine a density or other quantity of white blood cells in the fluid.

17. The system of any one of claims 1-5, wherein the output device comprises a display configured to provide information regarding white blood cells detected in the fluid to provide an indication of infection to the subject.

18. The system of any one of claims 1-5, wherein the output device comprises an indicator light that activates when the detector detects white blood cells in the fluid to provide an indication of infection to the subject.

19. The system of any one of claims 1-5, wherein the output device is mounted on the housing of the detector device.

20. The system of any one of claims 1-5, wherein the detector device comprises a communication interface for communicating data from the detector to a remote location, the system further comprising: an electronic device remote from the detector device comprising a communication interface for receiving the data from the detector device, and wherein the output device is on the electronic device.

21. The system of any one of claims 1-5, wherein the detector device comprises a sensor positioned adjacent the cavity and a processor coupled to the sensor to detect fluid flowing through the interior of the chamber member before detecting white blood cells.

22. The system of claim 21, wherein the sensor comprises a temperature sensor and wherein the processor acquires data from the sensor to confirm temperature within the interior exceeds a predetermined threshold to confirm fluid is flowing.

23. The system of any one of claims 1-5, wherein the detector comprises a camera and wherein the detector device comprises a processor coupled to the camera to acquire images of the interior of the chamber member and to analyze the images to detect - 26 - fluid flowing through the interior of the chamber member before detecting white blood cells.

24. The system of claim 15, wherein the processor is configured to process the images by filtering the images to remove static artifacts from the images.

25. The system of claim 15, wherein the processor is configured to process the images by removing artifacts from the images that exceed a maximum size.

26. The system of claim 15, wherein the processor is configured to process the images by: a) combining a plurality of pixels into an averaged pooled pixel for image-by-image comparison; b) identifying artifacts within a predetermined size range to identify white blood cells; c) identifying centroids of the artifacts; and d) counting the centroids to identify a number of white blood cells in the image.

27. The system of claim 26, wherein the processor is configured to repeat steps a) to d) to generate and analyze multiple images.

28. The system of claim 27, wherein the processor is further configured to determine a concentration of white blood cells within the fluid based at least in part on the number of white blood cells identified in the images.

29. The system of claim 28, wherein the detector device further comprises a display, the processor coupled to the display for presenting information related to one or both of the number of white blood cells identified and the concentration.

30. A device for detecting peritonitis of a subject undergoing peritoneal dialysis using a drain line to drain fluid from the subject’s peritoneal cavity, the device comprising: a housing including a cavity for receiving a portion of tubing of the drain line; - 27 - a camera mounted to the housing adjacent the cavity for acquiring images of fluid passing through the tubing; a processor coupled to the camera for analyzing the images to detect white blood cells in fluid passing through the tubing; and an output device for providing an output related to the presence of white blood cells in the fluid.

31. A device for detecting peritonitis of a subject undergoing peritoneal dialysis using a drain line to drain fluid from the subject’s peritoneal cavity, the device comprising: a housing including a cavity for receiving a component of the drain line; a camera mounted to the housing adjacent the cavity for acquiring images of fluid passing through the component; a processor coupled to the camera for analyzing the images to detect white blood cells in fluid passing through the component; and an output device for providing an output related to the presence of white blood cells in the fluid.

32. The device of claim 31, further comprising a light source mounted to the housing for providing light to the camera.

33. The device of claim 32, wherein the light source is mounted to the housing adjacent the cavity opposite the camera such that light emitted by the light source passes through the component to the camera to backlight the images.

34. The device of claim 31, wherein the processor is configured to analyze the images to detect fluid flowing through the interior of the chamber member before analyzing the images to detect white blood cells.

35. The device of claim 31, further comprising a sensor positioned adjacent the cavity, the processor coupled to the sensor to detect fluid flowing through the interior of the chamber member before analyzing the images to detect white blood cells. - 28 -

36. The device of claim 35, wherein the sensor comprises a temperature sensor and wherein the processor acquires data from the sensor to confirm temperature within the interior exceeds a predetermined threshold to confirm fluid is flowing.

37. The device of any one of claims 30-36, wherein the processor is configured to analyze the images by one or more of: filtering the images to remove static artifacts from the images; removing artifacts from the images that exceed a maximum size; combining a plurality of pixels into an average pooled pixel value; identifying artifacts within a predetermined size range to identify white blood cells; performing a centroid function to identify artifacts corresponding to white blood cells for counting; counting artifacts within a predetermined size range to identify a number of white blood cells in the images; and determining a concentration of white blood cells within the fluid.

38. The device of any one of claims 30-36, wherein the processor is configured to process the images by filtering the images to remove static artifacts from the images.

39. The device of any one of claims 30-36, wherein the processor is configured to process the images by removing artifacts from the images that exceed a maximum size.

40. The device of any one of claims 30-36, wherein the processor is configured to process the images by: a) combining a plurality of pixels into an average pooled pixel value; b) identifying artifacts within a predetermined size range of the image to identify white blood cells; c) identifying centroids of the artifacts; and d) counting the centroids to identify a number of white blood cells in the image.

41. The device of claim 40, wherein the processor is configured to repeat steps a) to d) to generate and analyze multiple images. - 29 -

42. The device of claim 41, wherein the processor is further configured to determine a concentration of white blood cells within the fluid based at least in part on the number of white blood cells identified in the multiple images.

43. The device of claim 42, wherein the detector device further comprises a display, the processor coupled to the display for presenting information related to one or both of the number of white blood cells identified and the concentration.

44. The device of any one of claims 31-36, the housing comprises first and second housing portions movable between an open position to accommodate positioning the component in the cavity and a closed position wherein the detector is positioned adjacent the component.

45. The device of claim 44, wherein the housing comprises one or more features for preventing movement of the component member when positioned in the cavity and the housing portions are in the closed position.

46. The device of claim 44, wherein the housing comprises a locking mechanism for securing the housing portions in the closed position.

47. The device of claim 44, wherein the cavity is shaped to receive a chamber member comprising first and second ends connectable to a drain line extending from a subject’s peritoneal cavity and opposing walls enclosing an interior through which fluid flows when the first and second ends are connected to the drain line.

48. The device of claim 44, wherein the cavity is shaped to receive a portion of tubing from the drain line.

49. A system for detecting peritonitis of a subject undergoing peritoneal dialysis, comprising: a housing comprising a fluid path therethough that may be coupled to a drain line; a detector configured to detect white blood cells in fluid passing through the fluid path; - 30 - an output device for providing an output when the detector detects white blood cells in the fluid; and a drain bag configured to be coupled to the housing such that fluid passing through the fluid path is captured in the drain bag.

50. A system for detecting peritonitis of a subject undergoing peritoneal dialysis, comprising: a detector device comprising: a housing comprising a fluid path therethough that may be coupled to a drain line; a detector configured to detect white blood cells in fluid passing through the fluid path; and a communication interface for communicating data from the detector to a remote location; and an electronic device remote from the device comprising: a communication interface for receiving the data from the detector device; and an output device for providing an output when the detector detects white blood cells in the fluid.

51. A method for detecting peritonitis of a subject undergoing peritoneal dialysis using a peritoneal catheter communicating with the subject’s peritoneal cavity, comprising: coupling a detector device to a drain line providing a fluid path from the subject’s peritoneal cavity; and activating a detector of the detector device to detect white blood cells in fluid passing through the fluid path, the detector device providing an output related to whether the detector detects white blood cells in the fluid.

52. The method of claim 51, wherein coupling the detector device comprises: coupling a chamber member in line with tubing of the drain line; and positioning the chamber member within a cavity of the detector device such that a detector is positioned adjacent the chamber member. - 31 -

53. The method of claim 52, wherein coupling the chamber member comprises: coupling first tubing to an inlet of the chamber member and to the subject’s peritoneal catheter; and coupling second tubing to an outlet of the chamber member such that fluid from the subject’s peritoneal cavity flows along a fluid path through the peritoneal catheter, the first tubing, an interior of the chamber member and the second tubing.

54. The method of claim 53, further comprising coupling a drain bag to the second tubing to collect the fluid from the fluid path.

55. The method of claim 51, wherein coupling the detector device comprises positioning a portion of tubing of the drain line within a cavity of the detector device such that the detector is positioned adjacent the portion.

56. The method of claim 51, wherein coupling the detector device comprises positioning a component of the drain line within a cavity of the detector device such that the detector is positioned adjacent the component.

57. The method of claim 56, wherein, when the component of the drain line is positioned within the cavity, a light source of the detector device is positioned adjacent the component for providing light to the camera.

58. The method of claim 57, wherein the light source is positioned adjacent the component such that light emitted by the light source passes through the component to the detector.

59. The method of claim 56, wherein the detector comprises a camera for acquiring images of fluid passing through the component, and wherein, when the detector device is activated, the detector device analyzes images from the camera to confirm fluid is flowing through the component and, once confirmed, analyzes the images to detect white blood cells. - 32 -

60. The method of any one of claims 52-55, wherein the detector device comprises a sensor positioned adjacent the cavity and wherein, when the detector device is activated, the detector device analyzes data from the sensor to confirm fluid is flowing through the drain line before detecting white blood cells.

61. The method of any one of claims 51-58, wherein the detector comprises a camera that acquires images of fluid passing through the fluid path and a processor that processes the images to detect white blood cells.

62. The method of claim 61, wherein, when activated, the detector device performs one or more of: filtering the images to remove static artifacts from the images; removing artifacts from the images that exceed a maximum size; combining a plurality of pixels into an average pooled pixel value; identifying artifacts within a predetermined size range to identify white blood cells; performing a centroid function to identify artifacts corresponding to white blood cells for counting; counting artifacts within a predetermined size range to identify a number of white blood cells in the images; and determining a concentration of white blood cells within the fluid.

63. The method of claim 61, wherein, the processor processes the images by filtering the images to remove static artifacts from the images.

64. The method of claim 61, wherein the processor processes the images by removing artifacts from the images that exceed a maximum size.

65. The method of claim 61, wherein the processor processes the images by: a) combining a plurality of pixels into an average pooled pixel value; b) identifying artifacts within a predetermined size range of the image to identify white blood cells; c) identifying centroids of the artifacts; and d) counting the centroids to identify a number of white blood cells in the image. - 33 -

66. The method of claim 65, wherein the processor repeats steps a) to d) to generate and analyze multiple images.

67. The method of claim 66, wherein the processor determines a concentration of white blood cells within the fluid based at least in part on the number of white blood cells identified in the multiple images.

68. The method of claim 67, wherein the processor presents information related to one or both of the number of white blood cells identified and the concentration on a display.