RU2231071C2 - Method for predicting subarachnoid hemorrhage - Google Patents

Abstract

FIELD: medicine, liquorology.

SUBSTANCE: one should study cerebrospinal liquid, moreover, it is necessary to detect catalase activity and at its appearance in cerebrospinal liquid one should diagnose the availability of subarachnoid hemorrhage.

EFFECT: higher accuracy of diagnostics.

2 ex

Description

The invention relates to medicine, namely to the diagnosis of subarachnoid hemorrhage.

Currently, for the diagnosis of subarachnoid hemorrhage, the determination of the number of red blood cells in the cerebrospinal fluid is used, while 0.1 ml of cerebrospinal fluid is poured into 0.9 ml of physiological NaCl solution and the number of red blood cells in the Goryaev’s chamber is calculated in 5 large squares located diagonally and drawn on 16 little ones. The resulting number of cells is multiplied by a factor of 500 to obtain the number of red blood cells in 1 ml of cerebrospinal fluid. Thus, the number of cells increases spasmodically, and the presence of only 1 red blood cell at the border of these five squares increases the result from zero immediately to five hundred. Moreover, when re-examining the same cerebrospinal fluid when counting within the boundaries of five squares, there may not be a single cell and the result then is zero. A false positive result is also possible if “traveling blood” enters the cerebrospinal fluid (Yurishchev EP et al. Clinical liquorology in neurosurgery. Clinical laboratory diagnostics, 1995, No. 6, p. 105-107).

In the diagnosis of the presence and massiveness of subarachnoid hemorrhage, it is important that the count be carried out immediately after the cerebrospinal fluid sampling, until the red blood cell cytolysis has occurred.

The aim of the invention is to improve the accuracy of diagnosis of subarachnoid hemorrhage.

This goal is achieved by determining the activity of catalase in the cerebrospinal fluid, an increase in the activity of which in the cerebrospinal fluid indicates hemolysis of red blood cells in the cerebrospinal fluid, since normal activity of this enzyme in the cerebrospinal fluid is not determined. Catalase is an organ-specific enzyme for red blood cells, the activity of which is associated with 15% of their membrane and 85% with hemoglobin. It differs from the previously used method for the diagnosis of subarachnoid hemorrhage - counting the number of red blood cells - in that it is more objective, the counting of the result is from scratch, it will not give a false positive result when the blood enters the cerebrospinal fluid, since it contains fresh red blood cells that have not undergone hemolysis. Therefore, in this case, catalase does not exit into the cerebrospinal fluid and its activity in the cerebrospinal fluid is not determined. The study may not be carried out immediately after the cerebrospinal fluid sampling, which is necessary when calculating the number of red blood cells due to their rapid hemolysis, since the enzyme activity is stable, it does not require additional activation energy. A small amount of biomaterial is needed - 0.1 ml of cerebrospinal fluid.

The method is as follows. The patient takes cerebrospinal fluid obtained as a result of lumbar puncture, centrifuged at 1500 rpm for 15 minutes To 2 ml of a 0.03% hydrogen peroxide solution we add 0.1 ml of cerebrospinal fluid supernatant. Instead of cerebrospinal fluid, we add 0.1 ml of distilled water to a blank sample. The reaction is stopped after 10 minutes by adding 1 ml of a 4% solution of ammonium molybdate. The intensity of the developed color is measured on a photoelectrocolorimeter at a wavelength of 410 nm against a control sample, into which instead of hydrogen peroxide we add 2 ml of water. The activity of catalase cerebrospinal fluid calculated by the formula

E = (A _hol. -A _op. ) (V · t · K),

where E is the activity of catalase (mkat / l);

A _hall. and A _op. - extinction of single and experimental samples;

V is the volume of the introduced sample of 0.1 ml;

t is the incubation time of 600 s;

K - coefficient millimolar hydrogen peroxide concentration equal to 22.2 x 10 ³ mmol ^-1 · cm ^-1.

The appearance of catalase activity in the cerebrospinal fluid indicates the presence of subarachnoid hemorrhage.

This method can be performed in any laboratory, since the method does not require expensive reagents and equipment.

We give examples of the implementation of the claimed method.

Example 1. Patient F., 53, was beaten on June 24, 2001 and was hospitalized on the same day in a neurosurgical department in serious condition with complaints of headache, loss of consciousness. During the examination, he was conscious, disoriented, there were elements of sensory aphasia, pupils D = S, weak convergence on both sides. The face was symmetrical. Tendon reflexes no difference. There were no pathological stop and meningeal signs. HELL 160/90 mm Hg, pulse 84 beats / min, respiratory rate 20 per min. As a result of lumbar puncture, a red, cerebrospinal fluid was obtained, turbid, in which the protein level was 0.858 g / l, free hemoglobin - 0.017 g / l, bilirubin - 0 μmol / l, the number of leukocytes 98 cells / μl, red blood cells - 155000 cells / μl After the examination, the diagnosis was made: closed head injury, moderate brain contusion, massive subarachnoid hemorrhage. The activity of catalase in the cerebrospinal fluid was 81.3 mkat / L. On the 8th day after the injury in the cerebrospinal fluid, the protein level was 0.106 g / l, free hemoglobin - 0 g / l, bilirubin - 4.7 μmol / l, the number of leukocytes 108 cells / μl, the number of red blood cells 1500 cells / μl, activity catalase was 14.6 mkat / L.

Example 2. Patient P., 28 years old. June 18, 2001 entered the neurosurgical department in an unconscious state. During the examination, the patient was unconscious, sometimes incoherent speech appeared. The condition was regarded as serious, horizontal nystagmus was observed on both sides, pupils D = S, weak convergence on both sides. The face was symmetrical. Tongue in the midline. Tendon reflexes D are greater than S. No abnormal stop signs. Stiff neck at 2 cross fingers. Blood pressure 110/70 mm Hg, pulse 104 beats / min, respiratory rate 20 per minute. As a result of lumbar puncture, a red cerebrospinal fluid was obtained, turbid, in which the protein level was 0.231 g / l, free hemoglobin - 0 g / l, bilirubin - 0 μmol / l, the number of leukocytes - 37 cells / μl, erythrocytes - 22000 cells / μl.

After the examination, the diagnosis was made: open head injury, moderate brain contusion, subarachnoid hemorrhage, closed frontal bone fracture, sinus. The activity of catalase in cerebrospinal fluid was 74.6 mkat / L. On the 3rd day after the injury in the cerebrospinal fluid, the protein level was 0.182 g / l, free hemoglobin 0.27 g / l, bilirubin 0.017 μmol / l, the number of leukocytes 42 cells / μl, the number of red blood cells 85,000 cells / μl , catalase activity was 259.7 mkat / l.

Thus, the proposed method for the diagnosis of subarachnoid hemorrhage by determining the activity of catalase in cerebrospinal fluid provides a more accurate and early diagnosis of subarachnoid hemorrhage, is simpler and more convenient than known.

Claims (1)

A method for diagnosing subarachnoid hemorrhage, including a study of cerebrospinal fluid, characterized in that the activity of catalase is determined and, when it appears in the cerebrospinal fluid, the presence of subarachnoid hemorrhage is diagnosed.