The problem of fungal infections in the era of COVID-19 has acquired special significance. This infection, directly or indirectly, through the use of glucocorticoids and antibiotics in its treatment, as well as poorer self-management of chronic diseases, has led to a wide spread of risk factors for fungal diseases among people who have had a novel coronavirus infection. The article presents two cases of COVID-19-associated mycosis, more related to mucormycosis, which were diagnosed by ophthalmologists in the Volgograd region. In the first case, the severe course of rhino-orbito-cerebral form of mucormycosis required a number of surgical interventions and prolonged treatment in the intensive care unit. In the second case, the patient asked for help without signs of aggravation of the general condition, but with irreversible local manifestations. In both cases, the eyeball was removed. Morphological examination revealed aseptal ribbon hyphae of different diameters, branching mainly at right angles, more typical for fungi of the Mucorales family. Due to the severe consequences of the disease, clinicians, including ophthalmologists, need to be especially alertness in patients with the described symptoms and risk factors in the post-COVID period.

BACKGROUND:The current case report presents acute hemorrhagic necrotizing encephalopathy (AHNE) as an example of a fatal complication, the etiology of which could be coronavirus disease 2019 (COVID-19) with multiple organ damage along with the existing respiratory tuberculosis.CASE PRESENTATION:A male in his 20s had severe symptoms of central nervous system lesion, which developed against the background of COVID-19 and respiratory tuberculosis, for which he was treated in the intensive care unit. Autopsy confirmed that he died from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) associated AHNE in adults with severe fatal endothelial dysfunction and respiratory tuberculosis. The main morphological signs of brain damage were desquamative endotheliitis, thrombosis, parenchymal hemorrhagic necrosis, encephalitis, severe necrobiotic neuronal damage.CONCLUSION:The defeat of endothelial cells with the development of generalized endotheliitis in COVID-19, especially in conjunction with comorbid pathology, in particular tuberculosis, can lead to a fatal complication that affects the nervous system-AHNE. Therefore, it is worth paying close attention to the appearance of neurological symptoms in patients with a similar combination of diseases.

In connection with the ongoing pandemic of the novel coronavirus infection, the study of its morphopathology and the analysis of autopsy data are relevant. At the same time, attention should be paid to thromboses that play a significant role in the development of fatal outcomes in COVID-19, even taking into account the prescription of anticoagulant therapy to most patients.OBJECTIVE:To make an assessment of morphological changes and a statistical analysis of the structure of mortality in COVID-19 on the basis of autopsy results in the Volgograd Region in 2020.MATERIAL AND METHODS:The study was based on data from «The system for information on the work of the Volgograd Regional Autopsy Bureau» with a search for cases according to U07.1 code (the COVID-19 virus was identified) in January 1, 2020, to December 31, 2020, as well as on the autopsy materials of the Volgograd Regional Autopsy Bureau, and microscopic examination with photo fixation. Statistical processing was performed using the R programming language.RESULTS:During the above period, 1119 deaths were identified with a confirmed diagnosis of COVID-19. Anatomopathological examination of the autopsy material showed that 77.54% of cases had blood clots mainly in the vessels of the pulmonary microvasculature, often only in the single veins during the applied anticoagulant therapy.Analysis of variance indicated that the obtained result statistically significantly differed from the random distribution, and the probability of the presence of blood clots of specified localization was 3.17 times higher (CI 2.3-4.4; p<0.05) than their absence, as evidenced by logistic regression. In addition, perivascular and intra-alveolar diapedesis hemorrhages were noted in most fatal cases.CONCLUSION:Thus, this investigation has revealed that the high frequency of thrombosis detected in the presence of perivascular and intra-alveolar diapedesis hemorrhages in COVID-19 confirms the tendency of patients with a severe course of the disease to manifest hemostatic disorders, significant blood vascular endothelial injury, and obvious vascular impermeability.

Autopsy material and medical history were studied and analyzed in a 20-year-old male patient who had died from COVID-19 infection with the development of acute SARS-CoV-2-associated hemorrhagic necrotizing encephalopathy in adults with obvious endothelial dysfunction confirmed by virological examination of the autopsy material. In this case, the brain structures displayed the main found histopathologic signs: widespread vasculitis (endotheliitis) with varying degrees of segmental and total endothelial destruction; thrombosis mainly of the vessels of the microcirculatory bed; parenchymal hemorrhagic necrosis and inflammation (encephalitis); severe necrobiotic damage to neurons. Cerebrovascular immune damages and hypercoagulable states, which were observed in some acute viral neuroinfections, are the basis for the neurological complications of COVID-19. In this case of bicausal diagnosis (the presence of a comorbidity), the primary disease contributed to the acute progression of the background disease (secondary infiltrative tuberculosis with the development of specific pleuritis and pneumothorax with the addition of acute bilateral focal confluent bronchopneumonia with a history of undifferentiated immunodeficiency syndrome. Emphasis is laid on the possibility and importance of involving the brain structures in the process in COVID-19 for the timely diagnosis of emerging neurological disorders. A brief literature review is given.

Analyzed 2 deaths from pathological and forensic practice in order to show that comorbid diseases in young patients in the context of the COVID-19 pandemic increase the risk of an adverse outcome due to the potentiation of the systemic damaging action of the viral agent, decompensation of chronic therapeutic pathology, the development of acute complications and status, possible drug interactions. The management of this category of patients requires knowledge of the characteristics of a viral infection, its clinical manifestations in combination with comorbid diseases.

Background The development of the eye and brain from one germ layer, the community of etiopathogenetic and morphological manifestations of age‐related macular degeneration (AMD) and Alzheimer's disease (AD), the common pathway of β‐amyloid precursor protein (APP) are associated with pathological aggregation of fibrillar β‐amyloid protein (Aβ ) and the development of β‐amyloidopathy in the structural elements of the eye and brain. Method Using electron microscopy and selective methods for detecting amyloid and its proteins, 111 eyes with morphological signs of AMD and a brain taken from 56 corpses were examined. Result Our studies have shown that senile amyloidosis of the eye in combination with senile cerebral amyloidosis occurs in the eighth decade of life, and their frequency increases with age. The cumulative accumulation of β‐amyloid deposits in the structures of the eye and brain was detected in 50.6% of cases. Amyloid‐β deposits were specific for eye druses from AMD and for senile plaques in brain tissue in patients with AD (Fig. 1, 2). In AMD, amyloid deposits are most often found in the Bruch membrane (64.5%) (Fig. 3). Vascular vessels (61.2%) took second place in frequency of occurrence (Fig. 4, 5). The combination of local forms of amyloidosis was characterized by concomitant deposition of β‐amyloid in the vessels of the brain and vessels of the choroid (amyloid angiopathy), as well as in the structural elements of the back of the eye and brain with a typical histochemical characteristic of local forms of senile amyloidosis. Moreover, amyloid angiopathy was more pronounced in the vessels of the brain than in the vessels of the choroid (Fig. 6). Conclusion The authors demonstrated that changes in the vessels of the brain and the structural elements of the retina and choroid in patients with AMD with AD can be considered as concomitant neurodegenerative processes in these two diseases, which are based on pathological aggregation of β‐amyloid protein. This view of the problem creates the prerequisites for the development of new strategies for the creation of ophthalmogeriatric and neuroprotective drugs that affect pathogenesis and include all stages of Aβ formation and pathological aggregation.

THE AIM OF THE STUDY:Is to draw the attention of forensic experts and histologists to the problem of infectious diseases occurring with the formation of granulomas. Was reviewed the general patterns of granulomatous diseases, as well as the peculiarities of pathomorphosis in helminthiasis (schistosomiasis, paragonimiasis, onchocerciasis, dirofilariasis, ascariasis, cysticercosis), mycoses (cryptococcosis, chromomycosis, coccidioidosis) and protozoal diseases, toxosomes. The article includes photomicrographs from the authors' personal archive, including those collected during their work in African countries Text is based on scientific data from articles, monographs, educational literature, personal experience and cases of forensic medical practice.