Vol 28, No 5 (2023)

Background: Tick-borne encephalitis and Lyme borreliosis are the most common natural focal infections in Russia often arising as a mixed infection, which is often clinically difficult to distinguish from a monoinfection at the onset of the disease that is a result of delayed laboratory verification of the diagnosis and it requires further searching for fundamentally new approaches to the issue of early differential diagnosis of tick-borne infections.
Aims: is to develop decision tree algorithms for early differential diagnosis between the mono- and mixed forms of acute Lyme borreliosis and tick-borne encephalitis with prevailing febrile syndrome in clinical picture based on clinical and laboratory data.
Materials and methods: We retrospectively analyzed 55 clinical and laboratory parameters obtained from 291 hospitalized tick-borne infections patients with or without erythema migrans at the site of ixodid tick bites in the first week of the disease, who were included in the single-center study from 2010 to 2023. In 211 patients without erythema, the analysis was carried out between three classes depending on the diagnosis: the mixed infection of non-erythematous Lyme borreliosis and tick-borne encephalitis, the mono-infection of non-erythematous Lyme borreliosis or the monoinfection of tick-borne encephalitis. The other two classes, which included 80 patients with erythema, had the mixed infection of acute erythematous Lyme borreliosis and tick-borne encephalitis or erythematous Lyme borreliosis monoinfection. Python programming language was applied to develop two decision tree models. Feature importance was assessed for all predictors. Each patient class was randomly divided into training (70%) and testing (30%) datasets. Accuracy evaluation of the models was based on ROC analysis.
Results: The decision tree algorithm for early differential diagnosis among the tick-borne infection patients without erythema migrans included the following most important predictors: maximal fever rise, chills, neutrophil-to-monocyte ratio, ESR, absolute number of reactive lymphocytes and immature granulocytes, and percentage of eosinophils. The model for differential diagnosis between the patients with erythema migrans included the following predictors: maximal fever rise, the absolute number of reactive lymphocytes and immature granulocytes, and the percentage of basophils. Both decision tree models showed excellent predictive values based on sensitivity, specificity, precision, accuracy, and F1 scores, as well as areas under the ROC curve, which were higher than 0.90.
Conclusions: Based on clinical and laboratory parameters, two decision tree models with high sensitivity have been developed, which can be easily applied in clinical practice for early differential diagnosis of the tick-borne infections with prevailing fever syndrome.

Rationale. Monitoring of HAI (health care-associated infections) detection and registration of is one of the key components in the information subsystem of epidemiological surveillance for these infections. Despite a well-established HAI recording system in the Russian Federation as a whole, the constituents of the Ural and Siberian Federal Districts have different approaches to detection of these infections, which is confirmed by the final rating scores of their detection and registration.

Objective. We studied HAI detection and registration in the constituents of the Ural and Siberian Federal Districts for ranking and rating their systems of epidemiological HAI surveillance.

Materials and methods: The data of federal statistical monitoring forms No. 2 "Information on infectious and parasitic diseases" and No. 23-17 "Information on outbreaks of infectious diseases as well as from additional enquiry materials "Information on medical manipulations and cohorts treated" in 2018–2022 submitted by the Rospotrebnadzor offices of the respective Russian Federation constituents compared with the long-term and Russia’s nationwide averages. The quality of HAI registration in the healthcare institutions of the Ural and Siberian Federal Districts was rated using grouping by intensive incidence indicators, and the most significant groups of infections and risk cohorts were selected for analysis.

Results: The results of the HAI detection and registration by the most significant groups of infections and risk cohorts among the patients and healthcare workers were analyzed. The data on the group and outbreak HAI morbidity in the healthcare institutions are presented. The quality of HAI detection and registration in the constituents of the Ural and Siberian Federal Districts was rated, and the subjects were ranked with regard to the activity of their epidemiological surveillance system.

Conclusion: Active detection and registration of HAI cases over several years is typical for the healthcare institutions of Sverdlovsk and Chelyabinsk Oblasts as well as Yamalo-Nenets Autonomous District. Consistently low rating scores of the studied parameters are typical for the healthcare institutions of the Republics of Tyva, Altai and Krasnoyarsk Krai.

Lyme borreliosis is a group of transmissible infectious diseases that are similar in etiology, but diverse in clinical manifestations. The development of Lyme disease symptoms is due not only to the activity of the pathogen itself, but also to the result of its interaction with immune system of macroorganism. The first line of defense, represented by a variety of cellular and humoral components of innate immunity, is most rapidly involved in immune response, and it is it that seeks to limit dissemination of the causative agent from the initial site of infection. However, a wide range of protective surface proteins of Borrelia and a number of other structures aimed at avoiding immune mechanisms prevent the destruction of the pathogen. Not the last place in this dynamic process is occupied by ixodid ticks themselves, since the secret of their salivary glands has an inhibitory effect on a number of cells and complement system. In parallel with innate immunity, adaptive immune response factors are activated, serving as a second line of defense. The synthesis of specific antibodies in the early period of Lyme disease has its own ambiguous features, but this does not exclude their importance in fight against borreliosis infection. To date, the issues of interaction with dendritic cells and cytotoxic T-lymphocytes remain less studied. Research of all aspects, including little-studied ones, is extremely important for both practical healthcare and fundamental medicine.

The article presents a clinical and morphological description of a case involving death upon admission to a hospital, marked by developed sepsis and septic shock caused by the addition of bacterial flora. It also presents a clinical and morphological description of the development of “shock organs — lungs and heart” after infection with SARS-CoV-2.

A 38-year-old patient was hospitalized diagnosed with severe coronavirus infection, leading to shock. Complications arising from the underlying disease included bilateral viral interstitial pneumonia. Virological analysis of throat and nose swap samples confirmed SARS-CoV-2 coronavirus RNA. The patient’s condition, evaluated on the NEWS2 scale, scored 18 points. C-reactive protein levels were measured at 117 mg/l, and procalcitonin level was 9 ng/ml. Despite treatment efforts, the patient did not survive. Sectional examination in the lungs showed focal atelectasis of various sizes, edema with a large number of red blood cells. In the alveoli, there are fibrin threads and “hyaline membranes” — blood stasis in the microcirculatory bed. In the heart, uneven blood filling in vessels, subendocardial hemorrhages, dystrophic and necrobiotic changes in cardiomyocytes, small foci of necrosis, fragmentation of cardiomyocytes, and intermuscular edema were noted. In the described case, the patient developed an infectious-toxic shock with severe changes in the lungs and heart attributed to a SARS-CoV-2 infection. These changes were intensified because of the addition and activation of bacterial flora due to a violation of the barrier function of the lung epithelium, leading to its complete destruction.

On August 11, 2023, at the age of 79 years, Alexander Markusovich Bronstein, Doctor of Medical Sciences, Professor of the Department of Infectious Diseases and Epidemiology of the Faculty of Medicine of the Russian National Research Medical University named after N.I. Pirogov, who worked on the editorial board of our magazine for more than a quarter of a century.