ABSTRACT
Introduction and aim. COVID-19 is a viral infectious disease, which was first reported in patients with unusual pneumonia in December 2019. However, as the pandemic progressed, extrapulmonary manifestations including various neurologic complications have been started to be increasingly reported. In this retrospective study, we tried to search the neurological complications seen in our patients with positive rRT-PCR test for COVID-19 and examine the underlying associated risk factors. Material and methods. We have retrospectively analyzed the neuroimaging studies performed in our patients with positive rRT-PCR test for COVID-19 between April, 2020 and August, 2021. Both computed tomography (CT) scans and magnetic resonance imagings (MRI) of brain, head & neck region and the spine were retrospectively evaluated for the presence of any complications in patients with positive rRT-PCR test for COVID-19. Results. There were 147 patients having neuroradiological imaging studies performed for various neurological symptoms. Among these patients we detected 10 acute neurologicalcomplications.The most common was acute ischemic stroke in 5 patients and intracranial hemorrhage in 3 patients, two of which were intraventricular hemorrhage. The other complications included a preasumed cytotoxic lesion of corpus callosum in a 18 year old girl and lumbar spondylodiscitis complicated with psoas abcess in a 47 year-old man. Conclusion. In COVID-19 patients severe neurological complications can occur even as a presenting manifestation. Early cytotoxic endothelial injury can be the underlying cause in these patients and should be further studied in larger series in terms of what the susceptibility factors in these patients. © 2022 Publishing Office of the University of Rzeszow. All Rights Reserved.
ABSTRACT
It was noticed that the mortality rate of SARS-CoV-2 infection experienced a significant declination in the early stage of the epidemic. We suspect that the sharp deterioration of virus toxicity is related to the deletion of the untranslated region (UTR) of the virus genome. It was found that the genome length of SARS-CoV-2 engaged a significant truncation due to UTR deletion after a mega-sequence analysis. Sequence similarity analysis further indicated that short UTR strains originated from its long UTR ancestors after an irreversible deletion. A good correlation was discovered between genome length and mortality, which demonstrated that the deletion of the virus UTR significantly affected the toxicity of the virus. This correlation was further confirmed in a significance analysis of the genetic influence on the clinical outcomes. The viral genome length of hospitalized patients was significantly more extensive than that of asymptomatic patients. In contrast, the viral genome length of asymptomatic was considerably longer than that of ordinary patients with symptoms. A genome-level mutation scanning was performed to systematically evaluate the influence of mutations at each position on virulence. The results indicated that UTR deletion was the primary driving force in alternating virus virulence in the early evolution. In the end, we proposed a mathematical model to explain why this UTR deletion was not continuous.