Severe Neurologic Complications of SARS-CoV-2

Morphologic Findings in the Cerebral Cortex in COVID-19: Association of Microglial Changes with Clinical and Demographic Variables

Despite the enormous interest in COVID-19, there is no clear understanding of the mechanisms underlying the neurological symptoms in COVID-19. Microglia have been hypothesized to be a potential mediator of the neurological manifestations associated with COVID-19. In most existing studies to date, morphological changes in internal organs, including the brain, are considered in isolation from clinical data and defined as a consequence of COVID-19. We performed histological immunohistochemical (IHC) studies of brain autopsy materials of 18 patients who had died from COVID-19. We evaluated the relationship of microglial changes with the clinical and demographic characteristics of the patients. The results revealed neuronal alterations and circulatory disturbances. We found an inverse correlation between the integral density Iba-1 (microglia/macrophage-specific marker) IHC staining and the duration of the disease (R = -0.81, p = 0.001), which may indicate a reduced activity of microglia and do not exclude their damage in the long-term course of COVID-19. The integral density of Iba-1 IHC staining was not associated with other clinical and demographic factors. We observed a significantly higher number of microglial cells in close contact with neurons in female patients, which confirms gender differences in the course of the disease, indicating the need to study the disease from the standpoint of personalized medicine.

Adult immunization practices, challenges and opportunities in Central America and the Caribbean: Advisory board proceedings

As individuals age, they become increasingly prone to infectious diseases, many of which are vaccine-preventable diseases (VPDs). Adult immunization has become a public health priority in the modern era, yet VPDs vaccination rates for adults are low worldwide. In Central America and Caribbean, national recommendations and vaccination practices in adults differ across countries, and adult vaccination coverage data are limited. An advisory board comprised infectious disease experts, pulmonologists, geriatricians, occupational health, and public health professionals for Central America and Dominican Republic was convened to: a) describe adult immunization practices in these countries; b) discuss challenges and barriers to adult vaccination; and c) find strategies to increase awareness about VPDs. The advisory board discussions reflect that national immunization guidelines typically do not include routine vaccine recommendations for all adults, but rather focus on those with risk factors. This is the case for influenza, pneumococcal, and hepatitis B immunizations. Overall, knowledge lacks about the VPD burden among health-care professionals and the general public. Even more, there is insufficient information on vaccinology for students in medical schools. Actions from the responsible authorities - medical schools and scientific societies which can advocate for vaccination and a better knowledge in vaccinology - can help address these issues. A preventive medicine culture in the workplace may contribute to the advancement of public opinion on vaccination. Promoting vaccine education and research could be facilitated via working groups formed by disease experts, public and private sectors, and supranational authorities, in an ethical and transparent manner.

Ischemic and Hemorrhagic Cerebrovascular Events Related to COVID-19 Coagulopathy and Hypoxemia

Since the very beginning of the COVID-19 pandemic, numerous researchers have made an effort to determine the molecular composition of the SARS-CoV-2 virus, and the exact pathomechanism through which the virus exerts such a devastating effect on the host/infected organism. Recent scientific evidence highlights the affinity of the virus towards ACE2 receptors, which are widespread in multiple human systems, including the central nervous system (CNS) and cerebral vessels. Such an affinity may explain endothelial dysfunction and damage that is observed in COVID-positive patients in histopathological studies, with subsequent dysregulation of the cerebral circulation leading to transient or acute cerebrovascular accidents. In this paper, we aimed to evaluate the effects of COVID-related hypoxemia and direct viral invasion on the cerebral circulation, with special respect to the postulated pathomechanism, vulnerable groups of patients, clinical course and outcomes, as well as diagnostic imaging findings.

Autoimmune encephalitis as a complication of COVID-19 infection: a case report

Background

During COVID-19 pandemic, a lot of newly discovered symptoms and presentations are emerging. Neurological symptoms of corona virus disease 19 (COVID19) have been reported including central nervous symptoms (CNS), peripheral nervous symptoms (PNS), and skeletal muscular symptoms; however, data are scarce about the exact occurrence of neurological affection during COVID-19 infection.

Case presentation

We present a case of a 67-year-old male patient with proven COVID-19 infection who developed acute confusion state, behavioral changes, agitation, and one attack of loss of consciousness 8 days following the infection. Laboratory profile, computed tomography (CT) brain, magnetic resonance imaging (MRI), and cerebrospinal fluid (CSF) analysis all were normal, and the patients were highly suspicion of autoimmune encephalitis due to COVID-19 infection. The patient received pulse steroid therapy with complete regaining the conscious level.

Conclusion

This clinical case emphasizes the possible relationship between COVID-19 infection and autoimmune encephalitis.

The Role of Von Willebrand Factor in the Pathogenesis of Pulmonary Vascular Thrombosis in COVID-19

The increased plasma levels of von Willebrand factor (VWF) in patients with COVID-19 was reported in many studies, and its correlation with disease severity and mortality suggest its important role in the pathogenesis of thrombosis in COVID-19. We performed histological and immunohistochemical studies of the lungs of 29 patients who died from COVID-19. We found a significant increase in the intensity of immunohistochemical reaction for VWF in the pulmonary vascular endothelium when the disease duration was more than 10 days. In the patients who had thrombotic complications, the VWF immunostaining in the pulmonary vascular endothelium was significantly more intense than in nonsurvivors without thrombotic complications. Duration of disease and thrombotic complications were found to be independent predictors of increased VWF immunostaining in the endothelium of pulmonary vessels. We also revealed that bacterial pneumonia was associated with increased VWF staining intensity in pulmonary arterial, arteriolar, and venular endothelium, while lung ventilation was an independent predictor of increased VWF immunostaining in arterial endothelium. The results of the study demonstrated an important role of endothelial VWF in the pathogenesis of thrombus formation in COVID-19.