RU2440577C1 - Method of early diagnostics of viral pneumonia - Google Patents

Abstract

FIELD: medicine. ^ SUBSTANCE: method of early diagnostics of viral pneumonia lies in counting quantity of desquaminated endothelial blood cells (DEC) and blood leukocytes (Leu) with further calculation of integral coefficient by formula: C=DEC/(In Leu). If coefficient value is >4.0, viral pneumonia is diagnosed. ^ EFFECT: method makes it possible to increase accuracy of early viral pneumonia diagnostics, method is highly informative, as it does not take much time and can be used without large expenditure in examination of a great number of patients. ^ 4 ex, 5 tbl

Description

The invention relates to medicine, namely to pulmonology, and can be used for early diagnosis and prediction of the course of viral pneumonia in influenza.

Influenza is an acute anthropic viral infection of the respiratory tract that occurs in all regions of the planet. It manifests itself in the form of seasonal epidemic outbreaks and epidemics. Several times a century pandemics occur, affecting tens of millions of people. The main complication of influenza is viral pneumonia (CAP), the development of which causes the severity of the condition of the patients and in some cases death. In the USA, the average mortality rates during the period of seasonal flu rises in 1990-99. accounted for more than 3,000 cases per year

[one]. In 2009-2010, during the pandemic of influenza A (H1N1), a large number of complicated forms of infection were observed, manifested by the development of CAP, more than 18,000 deaths were recorded only in laboratory-confirmed cases of highly pathogenic influenza [2]. According to modern clinical protocols for treating CAP, antiviral drugs should be prescribed within 48 hours from the onset of the disease, however, laboratory confirmation of the pathogen can last up to 5-7 days or more.

Therefore, early diagnosis of viral pneumonia is extremely important for the timely appointment of etiotropic (antiviral) therapy, which to a greater extent ensures recovery [3].

A known method for determining the severity of community-acquired pneumonia - patent No. 2302637 RU G01N 33/68. The invention consists in determining the reactivity of immunocompetent cells with determining the systemic level of cytokines (IL-2, IL-8, TNF-α). Severe pneumonia is diagnosed at a level of IL-2 from 15.78 to 17.98 pg / ml, IL-8 from 146.4 to 170.2 pg / ml, TNF from 11.73 to 12.73 pg / ml. This method of diagnosing community-acquired pneumonia and determining the severity of the course of the disease is a relevant, reliable, informative diagnostic method. However, this method is not accurate enough, because does not take into account all the mechanisms of development of viral pneumonia. In addition, determining the level of cytokines is a long and laborious process (performed by enzyme-linked immunosorbent assay - ELISA).

A known method for determining the severity and prognosis of the development of complications of pneumonia is patent No. 2290075 RU A61B 10/00. A patient is interviewed, 5 parameters of the anamnesis are evaluated on a 5-point scale, followed by a calculation of the prognostic probability of developing complications of community-acquired pneumonia. This technique is not informative enough, because It does not take into account all risk factors for severe CAP: overweight and obesity, type 2 diabetes mellitus and pregnancy (especially the third trimester), in most cases, severe CAP developed in young people who were previously completely healthy [4].

As a prototype, a diagnostic method for acute pneumonia No. 2082980 RU G01N 33/53 was taken, which consists in counting granulocytes and lymphocytes by phase contrast microscopy in a Goryaev’s chamber. These blood parameters are assessed by a cytolucogram and, when four connected granulocytes are detected and when double sockets are reduced by 1.3-1.8 times relative to the norm, acute pneumonia is diagnosed. The developed diagnostic method allows to obtain reliable data within 4 hours, does not require special sterility, scarce reactors, expensive devices and is easy to use. However, the method is not accurate enough, because It does not take into account all the mechanisms of development of viral pneumonia, and also does not allow predicting the severe course of the disease.

To increase the accuracy of the method for early diagnosis of viral pneumonia, the number of desquamated endothelial cells in the blood - (DEC) and leukocytes is counted, the logarithmic indicator of the number of leukocytes in the blood is calculated (ln Lei.), And the integral coefficient is calculated: K = DEC / (ln Lei. ) With a value of this coefficient> 4.0, the presence of clinical symptoms of influenza and physically and / or radiologically confirmed lung tissue infiltration, viral pneumonia is diagnosed.

The method is as follows: in a patient with flu symptoms and physically and / or radiologically confirmed lung tissue infiltration, venous blood is taken into a citrate tube. The number of desquamated endotheliocytes is calculated according to the classical method of Hladovec (1978). The method is based on the isolation of cells together with platelets, followed by platelet deposition using adenosine diphosphate (ADP). According to the author of the methodology, the normal amount of DEC does not exceed 2-4 in 1 microliter. Count the total number of peripheral blood leukocytes by light microscopy using methylene blue staining. Leukopenia <4.0 × 10 ⁹ is a rather specific sign of CAP [5].

The number of leukocytes is subjected to a logarithmic transformation, and then the coefficient is calculated by the formula: K = DEK / (ln Lei.).

This coefficient is complex and allows, on the one hand, to assess the degree of endothelial dysfunction, and on the other hand, the degree of immunosuppression in patients with CAP. This coefficient reflects the various mechanisms of viral infection and has the highest predictive value than indicators of the number of DEC and peripheral blood leukocytes separately.

The characteristic features of viral pneumonia in influenza, in contrast to banal community-acquired pneumonia, are endotheliosis (damage to vascular endothelial cells with their desquamation) and leukopenia due to immunosuppression. The endothelium - the inner lining of the vessels - consists of approximately 1-6 × 10 ¹³ cells. The vascular intima endothelium performs barrier, secretory, hemostatic, vasotonic functions, plays an important role in the processes of inflammation and remodeling of the vascular wall. The endothelium is a functional barrier between the vascular wall and the circulating blood, consisting of a single layer of cells. It produces a number of factors that regulate vascular tone, cell adhesion, thrombotic resistance, smooth muscle cell proliferation, and inflammation of the vessel wall. Thus, endothelium is of great importance in maintaining homeostasis [6]. Under the influence of various factors, including viral agents, the endothelium is activated with the release of biologically active substances that trigger inflammatory processes, followed by swelling and desquamation of the endothelium.

According to recent morphological studies, the influenza virus has a cytotoxic effect on the epithelium of the trachea, bronchi, alveoli, and also the endothelium of the vessels of the large and small circles of blood circulation. This is evidenced by the increased permeability of endothelial and epithelial cells that regulate water-electrolyte metabolism of the distal airway, which is accompanied by the sweating of plasma and blood cells through the wall of capillaries of the alveolar septa. The clinical manifestation of these disorders is the development of non-cardiogenic pulmonary edema - adult respiratory distress syndrome (RDSV) [7]. Endothelial dysfunction caused by influenza virus invasion is a key element in the pathogenesis of CAP. One of the signs objectively reflecting the degree of endothelial dysfunction is the amount of desquamated endotheliocytes in the blood.

The obtained parameters are interpreted as follows:

A) when the value of the coefficient DEC / (ln Lei.)> 4.0; the presence of flu symptoms and physically and / or radiologically confirmed lung tissue infiltration are diagnosed with viral (viral-bacterial) pneumonia;

B) with an increase in the DEK / (ln Lei.) Indicator in dynamics, its values> 10.0 diagnose severe forms of VP.

Table 1 Blood counts for various types of pneumonia Indicator Patients with various etiological factors in the development of pneumonia VP of mild to moderate severity (n = 76) Severe VP (n = 45) Community-acquired pneumonia of mild to moderate severity (n = 15) Severe community-acquired pneumonia (n = 15) Blood DEC level 8.33 ± 2.25 * 17.2 ± 5.66 * # 3.2 ± 0.6 5.1 ± 1.4 White blood cell count 6.2 ± 2.8 4.2 ± 2.4 * # 9.6 ± 4.2 14.7 ± 5.5 K = DEC / (ln Lei.) 4.65 ± 1.34 * 11.09 ± 6.08 * # 1.45 ± 0.62 2.01 ± 0.75 * - significant difference from community-acquired pneumonia (p <0.05)
# - significant difference from mild to moderate VP (p <0.05)

This method of diagnosing and assessing the severity of CAP was developed on the basis of a study conducted in 121 patients with an established diagnosis of viral pneumonia on the basis of the 1st City Clinical Hospital in Chita, the Road Clinical Hospital st. Chita-II and Regional Clinical Hospital No. 1 of the city of Chita.

All patients had flu-like symptoms, as well as physically and / or radiologically confirmed lung tissue infiltration. In all cases, the method of polymerase chain reaction (PCR) was detected RNA of influenza A virus (H1N1), which confirmed the diagnosis of VP. In addition to general clinical examination, all patients underwent counting of blood counts and leukocytes.

It was noted that with an increase in K, the severity of the condition of the patients increased; among patients with a coefficient K> 10.0 upon admission to the hospital, severe viral pneumonia was diagnosed in 95.6% of cases.

The control group consisted of 30 patients with community-acquired pneumonia hospitalized after the end of the epidemic (January-February 2010). There was no pronounced endotheliosis or leukopenia in the control group, the coefficient K = DEC / (ln Leu.) Was 1.45 ± 0.62 among mild and moderate pneumonias, 2.01 ± 0.75 among severe community-acquired pneumonia.

To assess the prognostic capabilities of all statistically significant studied parameters, a test was calculated using the predictive value of a positive result (PCR) and the predictive value of a negative result (PCR).

PCR - the proportion of patients with viral pneumonia among those with a coefficient of DEC / (ln Lei.)> 4.0.

PCOR - the proportion of patients with banal community-acquired pneumonia among those with a DEC coefficient / (ln Lei.) <4.0.

In patients with various types of pneumonia, the predictive value of a positive result was 96.7%, and the predictive value of a negative result was 87.5% (Table 2).

In addition, the following indicators were calculated (table 3):

- Sensitivity - the proportion of patients with a coefficient DEC / (ln Leu.)> 4.0 among those who have identified CAP = 93.3%.

- Specificity - the proportion of patients with a coefficient DEC / (ln Lei.) <4.0 among those who do not have CAP = 86.6%.

table 2 Prognostic possibilities of the level of DEC and blood leukocytes in various types of pneumonia DEC> 4.0 × 10 ⁴ / L Lei. <4.0 × 10 ⁹ / L DEC / (ln Lei.) PCR (%) 86.9 65.5 96.7 PCOR (%) 76,4 44 87.5

Table 3 Comparative characteristics of the level of DEC and blood leukocytes in various types of pneumonia DEC> 4.0 × 10 ⁴ / L Lei. <4.0 × 10 ⁹ / L DEC / (ln Lei.) Sensitivity (%) 92.5 24.7 93.3 Specificity (%) 87 83.3 86.6

Additionally, in order to assess the severity of CAP, the above parameters were also calculated: PCR and PCR.

PCR - the proportion of patients with severe viral pneumonia among those with a coefficient of DEC / (ln Lei.)> 10.0.

PCOR - the proportion of patients with mild and moderate viral pneumonia among those with a DEK / (ln Lei.) Coefficient <10.0.

In patients with CAP with influenza A (H1N1), the predictive value of a positive result was 95.6%, and the predictive value of a negative result was 78.5% (Table 4).

In addition, the following indicators were calculated (table 5):

- Sensitivity - the proportion of patients with a coefficient DEC / (ln Lei.)> 10.0 among those with severe CAP = 53.3%.

- Specificity - the proportion of patients with a coefficient DEC / (ln Lei.) <10.0 among those with mild and moderate EP = 98.6%.

Table 4 Prognostic possibilities of the level of DEC and blood leukocytes in patients with CAP with influenza A (H1N1). DEC> 10.0 × 10 ⁴ / L Lei. <10.0 × 10 ⁹ / L DEC / (ln Lei.) PCR (%) 81.8 52 95.6 PCOR (%) 66.3 72.5 78.5

Table 5 Comparative characteristics of the level of DEC and blood leukocytes in patients with CAP in influenza A (H1N1) DEC> 10.0 × 10 ⁴ / L Lei. <10.0 × 10 ⁹ / L DEC / (ln Lei.) Sensitivity (%) 46.7 33.3 53.3 Specificity (%) 87 64 98.6

Clinical example No. 1: Patient G. (39 years old) was admitted to the hospital during the flu epidemic as an emergency. Complaints were associated with dyspnea at rest, unproductive cough, high fever, runny nose, muscle pain, general weakness. From the anamnesis it was found out that about 5 days the patient had a SARS clinic, was treated symptomatically. Objectively: a serious condition, gray skin, body temperature - 39 °, respiratory rate (NPV) = 34-36 per minute, SpO ₂ = 80-82%, heart rate (heart rate) = 110 per minute, blood pressure ( HELL) = 110 and 70 mm Hg Auscultatory: bronchial breathing, crepitus below the angle of the shoulder blades on both sides, diffuse buzzing rales. A general blood test revealed leukopenia - 3.3 × 10 ⁹ / L, the number of DEC was 22.0 × 10 ⁴ / L, the coefficient of DEC / (ln Lei.) = 18.48 (severe viral pneumonia was suspected). According to chest x-ray, signs of bilateral pneumonia and adult respiratory distress syndrome (RDSV) were revealed. The patient was placed in the intensive care unit, intensive care was started. On the first day, a smear was taken for PCR for influenza A (H1N1), the next day a negative result was obtained. Despite this result, the patient was given two-component antiviral therapy, three-component antibacterial, symptomatic, detoxification therapy; subsequently, due to the progression of respiratory failure, mechanical ventilation with high PDKV values (positive pressure at the end of expiration) was initiated. However, despite intensive methods of respiratory support and drug therapy, on the 4th day of hospitalization, the patient died due to severe multiple organ failure. According to the results of the pathological study, viral pneumonia was morphologically confirmed, influenza A / H1-Swine RNA was detected in the sectional material by PCR, which confirms the diagnosis of influenza A / H1N1.

Clinical example No. 2: Patient L. (29 years old) was admitted to the hospital as an emergency in a period of decreased incidence of influenza. Complained of shortness of breath at rest, cough with mucous sputum, severe general weakness, sweating, dizziness. Within 3 days, the patient had an ARVI clinic, did not seek medical help, did not take antiviral drugs. On admission: a serious condition, the skin is pale, body temperature - 38.8 °, NPV = 32-34 per minute, SpO ₂ = 87-88%, heart rate = 112 per minute, blood pressure = 90 and 60 mm Hg Auscultation was determined by weakening of breathing in the lower sections on both sides, crepitus over all pulmonary fields. A general blood test revealed leukopenia up to 3.6 × 10 ⁹ / L, the number of DEC was 16.5 × 10 ⁴ / L, the coefficient of DEC / (ln Lei.) = 12.89 (severe viral pneumonia). On the chest radiograph - bilateral subtotal pneumonia, signs of RDSV. The patient was hospitalized in the intensive care unit. On admission, antiviral therapy and antibiotic therapy were prescribed, non-invasive ventilation was performed; a smear was taken on PCR for influenza A (H1N1) RNA, after three days a positive result was obtained. At that time, the patient's condition improved, the manifestations of respiratory failure decreased (NPV = 25 per min, SpO ₂ = 93%), hemodynamics were stabilized, the number of leukocytes increased to 5.5 × 10 ⁹ / l, the number of DEC decreased to 12.0 × 10 ⁴ / l, according to the radiograph - positive dynamics. After 20 days from the time of hospitalization, the patient was discharged for outpatient aftercare.

Clinical example No. 3: Patient N. (25 years old) was admitted to the hospital during the flu epidemic. Upon admission, she complained of shortness of breath during normal exertion, unproductive cough, runny nose, general weakness, sweating. She got sick about 2 days ago, did not take antiviral drugs. On admission: moderate severity, pale skin, body temperature - 38.3 °, NPV = 20 per minute, SpO ₂ = 94%, heart rate 96 per minute, blood pressure = 110 and 70 mm Hg. Auscultation was determined by weakening of breathing on the right below the angle of the scapula, in the same place small bubbling rales. In the general blood test, the number of leukocytes was 3.9 × 10 ⁹ / L, the number of DEC was 8.0 × 10 ⁴ / L, the coefficient of DEC / (ln Lei.) = 5.88 (EP of moderate severity). On the chest radiograph - interstitial lower lobar pneumonia on the right. The patient was hospitalized in the pulmonology department. Immediately upon admission, antiviral, antibacterial and symptomatic therapy was prescribed; swab taken for influenza A (H1N1) RNA. By the time a positive PCR result was obtained (after 5 days), the patient's condition was satisfactory. Normalization of all physical and laboratory parameters was noted; infiltration was not determined on the control radiograph. The patient was discharged on the 8th day of hospitalization with recovery.

Clinical example No. 4: Patient X. (23 years old) was admitted to the hospital during the flu epidemic. Upon admission, she complained of shortness of breath during normal exertion, dry cough, general weakness, sweating. She became ill acutely, after hypothermia, about 2 days ago. On admission: moderate severity, pale skin, body temperature - 38.6 °, NPV = 20-22 per minute, SpO ₂ = 93-95%, heart rate = 100 per minute, blood pressure 105 and 70 mm RT. Art. Auscultation was determined by weakening of breathing to the right below the angle of the scapula, sonorous crepitus. In the general blood test, the number of leukocytes was 12.2 × 10 ⁹ / L, the number of DEC - 3.0 × 10 ⁴ / L, the coefficient of DEC / (ln Lei.) = 1.2 (pneumonia, mainly of bacterial etiology). According to the chest radiograph - right-sided lower-lobe pneumonia. The patient was hospitalized in the pulmonology department. On admission, antiviral, antibacterial and symptomatic therapy was prescribed; swab taken for influenza A (H1N1) RNA. Three days later, a negative result was obtained, the patient was diagnosed with community-acquired pneumonia, antiviral drugs were canceled. Against the background of treatment, improvement of health was noted, radiological resolution of pneumonia. The patient was discharged on the 14th day with recovery.

Thus, for the diagnosis and assessment of the severity of viral pneumonia, the number of desquamated endothelial cells, the number of leukocytes are counted, and the integral coefficient is calculated: K = DEK / (ln Lei.) When this coefficient is> 4.0, viral pneumonia is diagnosed, with a value> 10 , 0 - severe course of viral pneumonia, which allows you to timely assess the condition of the patient and prescribe antiviral therapy.

Literature

1. Semenov B.F. The concept of delayed death in influenza and the tactics of vaccination for heart attacks, strokes and deaths with this infection. // Russian Medical Journal, t.11, No. 23, 2003, 1266-1268 p.

2. The official website of the World Health Organization. // http://www.who.int/csr/don/2010_05_21 /en/index.html

3. Information letter No. 24-0 / 10 / 1-5039 dated August 25, 2009 (as amended on November 03, 2009) - “Temporary guidelines of the Ministry of Health of the Russian Federation“ Schemes for the treatment and prevention of influenza caused by the A / H1N1 virus ".

4. Dominguez-Cherit G., Lapinsky S., Macias A.E. et all. Critically Ill patients with 2009 influenza A (H1N1) in Mexico. // JAMA 2009; Nov 4; 302: 1880-1887.

5. Belokrinitskaya T.E. et al. Intensive care of severe complicated forms of influenza A (H1N1) and seasonal flu in pregnant women. // Health. - 2010. - No. 1. - S. 39-47.

6. Influenza A / H1N1 as a typical emergent infection: A manual for doctors, ed. Kiseleva O.I. // S.Pb., 2009, 44 pp.

7. Zarubaev V.V. Morphological features of the infectious process in the lungs with influenza A (H1N1). // Materials of the Congress "Man and Medicine" April 12-16, 2010, Moscow.

Claims (1)

A method for the early diagnosis of viral pneumonia, including counting the number of white blood cells, characterized in that it further determines the level of desquamated endothelial blood cells, calculate the logarithmic indicator of the number of white blood cells and calculate the complex coefficient by the formula:
K = DEC / (ln Lei.), Where (DEC) is the number of desquamated endothelial cells, ln (Lei.) Is a logarithmic indicator of the number of blood leukocytes, with a coefficient value> 4.0, viral pneumonia is diagnosed.