[Endothelial dysfunction in COVID- 19 and cognitive impairment]

[Staging of COVID-19 morphological manifestations in lungs depending on disease duration]

OBJECTIVE

To determine morphological alterations in lung tissues in the case of novel coronavirus infection (COVID-19) in the aspect of process staging with consideration to disease duration.

MATERIAL AND METHODS

The number of COVID-19-related deaths of patients aged 55-65 years equal 17 were investigated. Serial cuts of lung tissue stained with hematoxylin and eosin, obtained from several lung fragments of each corpse, were analyzed. Morphological features previously described in literature sources were taken into account.

RESULTS AND CONCLUSION

It has been established, that processes in lungs have a phasic character, furthermore they are not clearly delimited in time. In addition, there were no morphological features specific to COVID-19. Obtained results may allow forensic medical experts-histologists to predict the COVID-19 duration.

Atherosclerosis, Cardiovascular Disorders and COVID-19: Comorbid Pathogenesis

The article describes how atherosclerosis and coronavirus disease 19 (COVID-19) may affect each other. The features of this comorbid pathogenesis at various levels (vascular, cellular and molecular) are considered. A bidirectional influence of these conditions is described: the presence of cardiovascular diseases affects different individuals' susceptibility to viral infection. In turn, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can have a negative effect on the endothelium and cardiomyocytes, causing blood clotting, secretion of pro-inflammatory cytokines, and thus exacerbating the development of atherosclerosis. In addition to the established entry into cells via angiotensin-converting enzyme 2 (ACE2), other mechanisms of SARS-CoV-2 entry are currently under investigation, for example, through CD147. Pathogenesis of comorbidity can be determined by the influence of the virus on various links which are meaningful for atherogenesis: generation of oxidized forms of low-density lipoproteins (LDL), launch of a cytokine storm, damage to the endothelial glycocalyx, and mitochondrial injury. The transformation of a stable plaque into an unstable one plays an important role in the pathogenesis of atherosclerosis complications and can be triggered by COVID-19. The impact of SARS-CoV-2 on large vessels such as the aorta is more complex than previously thought considering its impact on vasa vasorum. Current information on the mutual influence of the medicines used in the treatment of atherosclerosis and acute COVID-19 is briefly summarized.

Brain fog as a Long-term Sequela of COVID-19

Increasing data indicate that people infected with COVID-19 are at high risk for developing long-term neurological complications, such as "brain fog" or cognitive impairment. However, little is known about the long-term outcomes of COVID-19 survivors. This also applies to the prevalence, risk factors, and pathobiological findings associated with these consequences. Although cognitive complications are anticipated in patients who require a long-lasting hospital stay or intubation, milder cases of COVID-19 with no record of hospitalization have also been shown to experience assessable cognitive challenges. Cognitive impairment can have a devastating impact on daily functioning. Understanding the long-term effect of COVID-19 on cognitive function is vital for applying specific schemes to those who wish to return to their jobs productively.

[Clinical and pathophysiological features of stroke in patients with COVID-19]

OBJECTIVE

To study of modern literature on the clinical and pathophysiological features of stroke in patients with a new coronavirus infection (COVID-19).

MATERIAL AND METHODS

Published data were searched in the electronic databases Medline (PubMed) and eLIBRARY for the period 2019-2022.

RESULTS

It has been shown that patients with COVID-19 have a large number of risk factors for stroke, which may indicate that COVID-19 is a trigger for the development of the disease. Stroke predominantly occurs in 10-14 days after the onset of COVID-19, i.e. there was a delayed manifestation. Patients with stroke due to a COVID-19 are characterized by occlusion of large vessels or vessels, in which occlusion occurs extremely rarely, as well as the presence of several lesions. Specific laboratory signs are coagulopathy, the presence of antiphospholipid antibodies, as well as impaired liver and kidney function. This cohort of patients is characterized by high mortality and poor functional outcome (in more than 70% of cases). The pathogenetic mechanism underlying stroke has not been established yet, however, in patients with COVID-19, the activation of a cascade of blood coagulation and thrombosis reactions is recorded. Suppression of ACE2 due to the affinity of its receptors for the COVID-19 virus probably also plays a role in the pathogenesis of stroke, since when the virus enters the body, an imbalance of the renin-angiotensin system develops.

CONCLUSION

COVID-19 can lead to the development of various neurological diseases, including stroke. Further researches are needed to study neuropathogenesis of COVID-19 and the impact of virus SARS-CoV-2 on disease progression.

"Brain Fog" by COVID-19 or Alzheimer's Disease? A Case Report

Cognitive symptoms after COVID-19 have been increasingly recognized several months after the acute infection and have been designated as “brain fog.” We report a patient with cognitive symptoms that started immediately after COVID-19, in which cerebrospinal fluid biomarkers were highly suggestive of Alzheimer’s disease. Our case highlights the need to examine patients with cognitive symptoms following COVID-19 comprehensively. A detailed assessment combining clinical, cognitive, and biomarker studies may help disentangle the underlying mechanisms associated with cognitive dysfunction in each case. The investigation of neurodegenerative processes in an early stage, especially in older patients, is probably warranted.