Janus kinases inhibitors (JAKi) have an immunosuppressive effect due to the normalization of levels of proinflammatory cytokines, are used in the treatment of cytokine storm in COVID-19. This fact makes it necessary to search a predictor of an efficacy of this small-molecules.

   The aim of the study. To evaluate the possibility of using cytokines in predicting the efficacy of JAKi in COVID-19.

   Materials and methods. We examined 86 patients with COVID-19: 50 men and 36 women. The age was 57,0; (50,0–65,0) years. The SARS-CoV-2 presence was confirmed by PCR. The control group consisted of 30 healthy donors matched by sex and age. The criterion for the efficacy of JAKi was recovery, in efficacy – switching to another drug, or death. The serum concentration of IL-1β, –6, –8, –17, TNF-α and GM–CSF by ELISA was estimates using Invitrogen test-systems (USA), according to the manufacturer’s instructions.

   Results. In COVID-19 patients who received baricitinib (BTC), compared with healthy individuals, basal (before JAKi starting) IL-6, TNF-α serum concentrations were increased; tofacitinib (TFT) – IL-6, ruxilitinib (RLT) – IL-6 and TNF-α. A decrease of IL-1β and GM–CSF serum concentration was noted before the start of TFT and RLT. Basal concentrations of IL-6 and TNF-α are most statistically strongly associated with the diagnosis COVID-19. After 5 days of treatment with BTC, there was an increase in IL-8 level compared to the basal, a decrease in the GM–CSF concentration and a slight increase IL-6 concentration relative to healthy donors (p < 0.05 in all cases). Basal concentration of IL-17 (more than 13.9 pg/ml) indicated the possibility of successful RLT treatment (area under the ROC-curve = 0.99; AP = 99 %; DS = 80 %; OP+ = 5.0; OP– = 0.2; CI: 0.9–1.0).

   Conclusions. Basal serum concentration of cytokines may predict JAKi efficacy in COVID-19 patients.

   The study examines the relationship between the levels of laboratory serum markers of inflammation and severity in patients with COVID-19.

   The purpose of the study. To investigate the mechanisms of interaction of inflammatory markers and calculate their diagnostic effectiveness in patients with COVID-19 in assessing the severity and prognosis of the disease.

   Materials and methods. We conducted a retrospective cohort study of the blood of 104 patients aged 20–84 years admitted to the hospital. The patients were divided into groups: group 1 – mild degree (n = 14); group 2 – moderate degree (n = 50); group 3 – severe degree (n = 40). The concentration of procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6), presepsin (PSP), proadrenomedullin (MRpro-ADM), ferritin (F), components of the complement system C 3, C 4 were determined using original reagent kits on automated systems.

   Results. In the obtained results of primary studies in the general group, an increase in the average values of inflammatory markers from reference values was noted. Correlation analysis revealed reliable direct medium and weak connections between markers of inflammation. Threshold
values were obtained when comparing groups with mild and moderate severity for MRpro-ADM, PCT, F, and in the group with moderate and severe severity for PCT, PSP, CRP and IL-6, above which we can talk about the transition of the disease to a moderate and severe degree of the disease, respectively.

   Conclusions. Determination of concentration and threshold values with parameters of diagnostic sensitivity of acute-phase markers of inflammation serves as an additional criterion for assessing the severity of the disease, prognosis, monitoring of treatment, but not specific diagnosis and allows you to understand the mechanisms of the immune system response.

   The aim of the study. To determine the severity of the current COVID-19 in patients with CHF.

   Materials and methods. The study included data from 98 patients diagnosed with COVID-19 in combination with CHF. The data on the duration of hospitalization, the severity of the lesion, the dynamics of the level of laboratory parameters are analyzed.

   Results. In 68 patients with CHF 2A, stage I of CHF in 27 patients and in 3 patients – stage 0. CHF of functional class I – 23 patients, FC II – 73 patients, FC III – 2 patients. The average duration of hospitalization was 15 days. Blood saturation (SpO2) in the range of 95–100 % was determined in 75 patients, 90–95 % – in 20 people, less than 90 % – in 3 patients. In 42.86 % of patients, an increase in the level of D-dimer was detected according to laboratory studies.

   Conclusions. Patients 60 years and older with CHF 2A and FC II with pronounced clinical symptoms are at risk of severe infection requiring hospitalization. Concomitant diseases of the cardiovascular system increase the duration of hospitalization.

   Background. It is of interest to study in detail the consequences of COVID-19 in women, since there is evidence that female sex is a risk factor for post-COVID syndrome.

   The aim of the study. To study the subjective and laboratory manifestations of post-COVID syndrome in women depending on age and results for SARS-CoV-2.

   Materials and methods. One-time retrospective analysis of 281 medical records of women aged 20 to 91 was performed; WHO age groups are divided into test and control subgroups (confirmed and unconfirmed COVID-19, respectively). The questionnaire for post-covid syndrome, biochemical and clinical blood tests were evaluated. Statistical analysis was done using the Mann-Whitney test, Pearson’s χ², analysis of variance, Spearman’s correlation.

   Results. Women with proven COVID-19 were 1.5–2.0 times more likely to report a decrease in quality of life, exercise tolerance, cough, cardiac symptoms, edema, hair loss, skin rash, arthralgia. Laboratory-proven COVID-19 is associated with the severity of COVID-19, most of the above symptoms, increased ESR. The test subgroup of young women had higher ALT levels. In the test subgroup of middle age, a decrease in the quality of life and working capacity, hair loss and skin rash were 1.5 times more common. In the test subgroup of the elderly, diabetes mellitus was detected 2 times more often, and lower platelet counts were observed. Old women of the test subgroup have higher ESR, D-dimer and lower hemoglobin.

   Conclusions. The severity of post-COVID syndrome in women depends on the severity and laboratory confirmation of the transferred COVID-19, in contrast to the duration of its subjective manifestations. The greatest decrease in the quality of life after a significantly transferred COVID-19 is observed in middle-aged women. The control of laboratory parameters in post-covid syndrome in women should be differentiated depending on age.

   Background. Recently, the demand for the measurement of vitamin D has been growing at a rate outrunning other types of laboratory tests. However, estimates of the prevalence of this nutrient status among population groups vary widely, based on target levels considered adequate or optimal for maintaining good health. The lack of a unified approach to stratifying the values of vitamin D in a patient’s blood creates difficulties in assessing the status of this nutrient.

   Objective. Stratification of vitamin D results in pediatric and adult patients examined between 2017 and 2022 at the St. Petersburg Consultative and Diagnostic Centre for Children, using criteria of different research groups and professional societies.

   Materials and methods. Vitamin D measurements were carried out using an immunochemical analyzer from January 2017 to December 2022 in 15,946 samples from children and 9,163 from adults.

   Results. Using stratification criteria proposed by various research groups and professional societies, the range of vitamin D deficiency in 2017–2019 ranged from 3.0 % to 63.9 % in children and from 2.4 % to 81.7 % in adults. In 2020–2022 deficient status was less common for all criteria: from 0.2 % to 51.2 % in children and from 0.1 % to 42.5 % in adults. An inverse relationship was noted for vitamin D levels associated with risk of harm. In 2017–2019 such values were detected in 1.0 %, in 2020–2022 in 2.8 % of children. In adults, similar rates increased from 1.8 % in 2017–2019 up to 3.5 % in 2020–2022.

   Conclusions. The wide variation in approaches reflects the uncertainty in research findings, recommendations, and guidelines involving vitamin D. Consensus on vitamin D thresholds will help arrive at the most likely conclusions from an evidence-based clinical perspective when establishing an association between a risk factor and an outcome.

   Vitamin D plays an important role in maintaining human health and has many positive properties. Its deficiency can negatively affect the body and worsen the quality of life. Worldwide, deficiency of this vitamin is a widespread problem. Different states set their own reference values of vitamin D levels for their populations. The article considers the justifications underlying the establishment of recommendations for its level and the basic units of measurement of 25(OH)D. Understanding the differences in normal vitamin D values between countries makes it possible to more accurately adapt recommendations to specific populations and ensure that optimal vitamin D levels are achieved, which is necessary to maintain the health of the population.

   Automated analysis of effusion fluids, providing a large amount of objective information about a biological sample, has significantly expanded the diagnostic capabilities of the cytological service. At the same time, there are currently no unified algorithms for interpreting the obtained data.

   The aim of the work was to develop, based on the results of automated analysis of pleural fluids, alternative predictions of the genesis of the effusion (benign / malignant).

   The study was carried out on the basis of the Clinical Regional Hospital No. 2 in Krasnodar (Russia). The results of automated analysis of biological fluids obtained using the Sysmex XN analyzer were compared with the data of cytological, laboratory and instrumental studies. The article presents some of our own developments that can serve as indicative criteria for interpreting the results of automated analysis of biological fluids. It has been established that in terms of differential diagnosis of the genesis of effusion, the indicators of total cytosis (TC-BF) and the absolute content of highly fluorescent mononuclear cells (HF-BF#) are the most informative. Accounting for clinical data, results of laboratory and instrumental studies increases the informative value of automated analysis of biological fluids.

   Hemorrhagic fever with renal syndrome and leptospirosis have similarities and differences in the clinical picture. Fever, intoxication, pronounced kidney damage and hemorrhagic syndrome are observed in both infections. The course of these diseases may be complicated by the development of infectious-toxic shock, acute renal failure, disseminated intravascular coagulation. Clinical manifestations of the syndrome of jaundice and meningitis may be observed in leptospirosis, but are not characteristic of hemorrhagic fever with renal syndrome. In leptospirosis, in contrast to hemorrhagic fever with renal syndrome, liver failure may develop. Infection with these diseases often occurs during a stay in a forest, in a holiday home, in rural areas. The natural foci of these infections may be located on the same territories or border each other, which also complicates the differential diagnostics. The article provides information on the etiology, epidemiology, geographical distribution, pathogenesis, pathological anatomy, clinical picture and diagnostics of hemorrhagic fever with renal syndrome and leptospirosis. Based on these data, the pathophysiological, clinical and laboratory aspects of the differential diagnosis between these diseases are analyzed in detail.

   The problem of the spread of syphilis is becoming acute due to the rapid increase in the number of initially detected cases of the disease. When analyzing and interpreting the obtained laboratory data, there is always the possibility of obtaining contradictory results, both false positive and false negative, which do not coincide with the clinical picture of the patient. Since in practice false positive results of serological tests for syphilis are detected more often than false negative ones, special importance is attached to the identification and study of the causes of their occurrence. At the analysis stage, the cause may be the cross-reactivity of the test system with various ‘particles’ in the analyzed samples, due to the peculiarities of its design and antigenic composition. For this work, sets of reagents Abbott GmbH (CMIA), Mindray (CLIA), as well as reagents produced by Vector-Best (ELISA) were used. During the study, it was found that one of the possible ‘particles’ leading to cross-reactivity of test systems may be IgG antibodies to cytomegalovirus.

   In order to improve the diagnosis of exacerbation and activity of sarcoidosis in patients receiving complex treatment, including corticosteroids, 303 patients with respiratory sarcoidosis were examined at the initial visit (before treatment) and every 2 months of treatment for 2 years. Group 1–193 patients without exacerbation of sarcoidosis; group 2–51 patients with exacerbation of sarcoidosis, who did not take corticosteroids (GCS); group 3–59 patients with exacerbation of sarcoidosis, long-term taking corticosteroids. In order to improve the diagnosis of exacerbation and activity of sarcoidosis in patients receiving complex treatment, including glucocorticosteroids, 303 patients with respiratory sarcoidosis were examined at the initial visit (before treatment) and every 2 months of treatment for 2 years. Group 1–193 patients without exacerbation; group 2–51 patients with exacerbation who did not take corticosteroids (GCS); group 3–59 patients with exacerbation, long-term taking corticosteroids. Conducted clinical and biochemical blood tests, computed tomography of the respiratory organs, spirography, echocardiography, electrocardiography at rest. Changes in the following serum markers were studied: free radicals (RwR), resistance to oxidative stress calculated by trolox equivalent (UcE), angiotensin-converting enzyme (ACE), adenosine deaminase (ADA), the correlation coefficient (CC) was calculated according to the developed formula (patent): CC = ACE/ADA in arbitrary units (KKnorm = 1.2–2.4), markers of lipid metabolism disorders were determined, to assess the activity of endogenous inflammation, the indicator of lipoidosis activity (PAL) was calculated according to the previously developed formula (patent): PAL = TC/LDLxc + TGL. Before treatment, 100 % of patients with sarcoidosis showed signs of moderate endogenous inflammation, an active granulomatous process, hypoxemia, and a decrease in the body’s antioxidant defense. The sensitivity of the serum adenosine deaminase (ADA) enzyme in exacerbations of sarcoidosis was 31 %, and the specificity was 48 %. The correlation coefficient (CC) had a sensitivity of 85.0 %; specificity 78.8 %; diagnostic efficiency of 80.0 % and higher clinical value than ACE, ADA, PAL, SVR, UKO. Thus, the serum enzyme adenosine deaminase (ADA) should be included in the mandatory minimum of laboratory methods in patients with sarcoidosis.

   Authors discuss the current state and prospects for the development of genetic testing in clinical laboratory diagnostics, recent nucleic acids sequencing technologies, their advantages and applications. Although genome-wide association studies (GWAS) have become a standard practice in identifying SNPs to determine disease susceptibility, this approach has limitations. A novel approach is proposed: integrative genome-wide association analysis (iGWAS), which relies on gene expression information to investigate the associations between SNPs and disease phenotype. Numerous studies have shown that iGWAS can significantly facilitate the search for genetic correlations and is superior to a method that relies only on the search for SNPs. Genetic testing will facilitate the molecular-based reclassification of human diseases. Authors describe the technical aspects of nanopore sequencing, the development of an iPhone app to complement miniature sequencing devices, and the world’s first mobile genomic sequence analyzer, iGenomics.