[Clinical and laboratory parameters and pathomorphological features of the lungs in patients who have had COVID-19 viral pneumonia]

Post-Covid syndrome is characterized by general somatic manifestations, changes in the psycho-emotional sphere, cognitive disorders, disorders of the cardiovascular, respiratory systems and excretory function. However, there is little information in the literature about the mechanisms of thanatogenesis in patients who have had COVID-19. An analysis of clinical and laboratory parameters and pathomorphological changes was carried out in 9 autopsy cases of patients who had previously suffered a new coronavirus infection (COVID-19). The age of the deceased ranged from 80 to 96 years. At the time of hospitalization, the concentration of IgG varied from 32.61 to 1013.5 RLU, IgM - from 0.29 to 16.98 U/ml. The period from clinical diagnosis to death ranged from 12 to 46 days, and the time from clinical recovery (negative polymerase chain reaction) to death ranged from 2 to 30 days. In all cases, unresolved viral pneumonia and diffuse alveolar damage (exudative-proliferative phase) were diagnosed.

COVID-19: Clinical laboratory diagnosis and monitoring of novel coronavirus infected patients using molecular, serological and biochemical markers: A review

COVID-19, a novel coronavirus disease, has provoked a variety of health and safety concerns, and socioeconomic challenges around the globe. The laboratory diagnosis of SARS-CoV-2 was quickly established utilizing nucleic acid amplification techniques (NAAT) after the disease causing virus has been identified, and its genetic sequence has been determined. In addition to NAAT, serological tests based on antibodies testing against SARS-CoV-2 were introduced for diagnostic and epidemiologic studies. Other biochemical investigations include monitoring of peripheral blood cells count, platelets/lymphocyte ratio, coagulation profile, cardiac, and inflammatory markers such as cytokines storm are also crucial in combating COVID-19 pandemic. Further, accurate and reliable laboratory results for SARS-CoV-2 play very important role in the initiation of early treatment and timely management of COVID-19 patients, provide support in clinical decision-making process to control infection, and detection of asymptomatic cases. The Task Force on Coronavirus-19 constituted by International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) has recognized informational framework for epidemiology, pathogenesis, and recommended the PCR-based analysis, serological and biochemical assays for analysis, monitoring, and management of disease. This literature review provides an overview of the currently used diagnostic techniques in clinical laboratories for the diagnosis, treatment monitoring, and management of COVID-19 patients. We concluded that each assays differ in their performance characteristics and the utilization of multiple techniques is necessary for the accurate diagnosis and management of SARS-CoV-2 infection.

Features of nervous system damage in antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune process that increases the risk of arterial and venous thrombosis. The mechanism of damage to the central nervous system (CNS) can be not only due to thrombosis, but also antiphospholipid antibodies (APA) circulating in the peripheral blood. The latter can damage the cerebral vascular endothelium, alter the resistance of the blood-brain barrier and penetrate into the central nervous system, exerting a damaging effect on astroglia and neurons, as evidenced by the release of neurospecific proteins into the peripheral bloodstream. The role of APS in developing cerebral ischemia, migraine, epilepsy, chorea, transverse myelitis, multiple sclerosis, cognitive impairment and mental disorders, as well as the peripheral nervous system is described. It should also be noted about a role of APS for emerging neurological disorders in COVID-19, enabled apart from thrombogenesis due to APA via 2 potential mechanisms - molecular mimicry and neoepitope formation. Further study of the APS pathogenesis and interdisciplinary interaction are necessary to develop effective methods for patient management.

Macrophage activation syndrome in COVID-19

The novel coronavirus epidemic is characterized by high rates of morbidity and relatively high mortality. Laboratory test results in patients include leukopenia, an increase in liver function tests and ferritin levels reaching hundreds, and sometimes thousands of units. These data remind us about the macrophage activation syndrome (MAC). Secondary hemophagocytic lymphohistiocytosis syndrome, MAC, which pathogenesis is based on a defect in the mechanisms of T-cell cytotoxicity and decreased level of natural killer cells associated with the defect in the perforin-encoding gene as well as hyperproduction of a number of cytokines – interleukin (IL)-1â, tumor necrosis factor-á, etc. by T-lymphocytes and histiocytes, indirectly leading to the activation of macrophages and production of proinflammatory cytokines, in particular IL-6 hyperproduction. MAC is one of "hyperferritinemic syndromes". These disorders have similar clinical and laboratory manifestations, and they also respond to similar treatments, suggesting that hyperferritinemia may be involved in the overall pathogenesis and is characterized by elevated ferritin level and cytokine storm. Despite the fact that data on the immune and inflammatory status in patients with COVID-19 have only started to appear, it is already clear that hyperinflammation and coagulopathy affect the disease severity and increase the risk of death in patients infected with SARS-CoV-2. Hence, understanding the pathogenesis of the novel coronavirus infection can help in its early diagnostics and treatment.

COVID-19, neutrophil extracellular traps and vascular complications in obstetric practice

An issue of the novel coronavirus infection spreading is currently in the first place among others in the list of the international medical community. Due to lack of information, conflicting research findings, multicomponent effect of the virus on the body host, as well as various consequences that the virus triggers in the body, now every medical specialty does study the viral attack pathogenesis. Recent months showed that vascular complications are the most severe in the Coronavirus Disease 2019 (COVID-19) and are the main cause of death in the patients. The mechanisms of vascular complications are complex and affect both the hemostatic system and immune responses, "inflammatory storm", disorders of the renin-angiotensin-aldosterone system, endotheliopathy, etc. Due to the leading role of vascular complications in the viral infection pathogenesis, several groups of patients are at extra risk, including pregnant women, patients with a burdened obstetric history, with hereditary thrombophilia and antiphospholipid syndrome, and patients after in vitro fertilization (IVF). In this category of pregnant women, use of low-molecular-weight heparins (LMWH) is particularly important for both prevention of vascular and obstetric complications, and for pathogenetic therapy of COVID-19.

Novel coronavirus infection and Kawasaki disease

There is a global problem of increment of the number of children with clinical features that mimic Kawasaki Disease (KD) during the ongoing Coronavirus Disease 2019 (COVID-19) pandemic. The disease was first reported by Tomisaku Kawasaki, a Japanese pediatrician, in a four-year-old child with a rash and fever at the Red Cross Hospital in Tokyo in January 1961. Now Kawasaki disease is recognized worldwide. The complexity of symptoms was defined as an «acute febrile mucocutaneous lymphnode syndrome". At the moment, it is still unclear whether the coronavirus itself can lead to development of mucocutaneous lymph node syndrome. However, it is believed that COVID-19 virus infection worsens the course of Kawasaki disease, and in some cases, children affected by SARS-V-2 may develop a disease that has a clinical picture similar to Kawasaki disease.