Background/Objectives: The Omicron variant of SARS-CoV-2 is undergoing constant mutation. New strains vary in neuropathogenicity and the neurological spectrum of disease. The aim of this study was to assess the frequency and clinical characteristics of neurological manifestations during the Omicron dominance among hospitalized patients, including the differences between three subsequent periods. Methods: This retrospective single-center study included 426 hospitalized adults with confirmed COVID-19 divided into three periods (O1, O2, and O3) dependent on the dominance of Omicron subvariants in Poland. Demographic and clinical data, in particular neurological manifestations, were collected and compared. Results: The median age of the group was 74, older in subsequent (later) periods. The number of patients with a history of previous SARS-CoV-2 infection or vaccination increased with the duration of the pandemic. The severity of COVID-19 became lower in successive periods. Neurological manifestations were observed in 55.4% of patients, and the most frequent were delirium, headache, myalgia, dizziness, cerebrovascular diseases, and encephalopathy. In subsequent periods of Omicron dominance, a higher frequency of neurological manifestations such as delirium, transient ischemic attack (TIA), and encephalopathy was observed. Headache or myalgia was related to a shorter hospitalization while delirium, cerebrovascular diseases, and ischemic stroke were linked with an increased risk of death. Conclusions: The Omicron variant of SARS-CoV-2 presents a wide spectrum of neurological manifestations. Although there is an improvement in the survival rate of patients with COVID-19, the frequency of neurological manifestations increases. The occurrence of delirium, cerebrovascular diseases, and ischemic stroke results in higher mortality.

Background/Objectives: SARS-CoV-2 continually mutates, with five identified variants. Many neurological manifestations were observed during the COVID-19 pandemic, with differences between virus variants. The aim of this study is to assess the frequency and characteristics of neurological manifestations during COVID-19 in hospitalized patients over three waves in Poland with comparison and analysis correlation with the course of infection. Methods: This retrospective single-center study included 600 consecutive adults with confirmed COVID-19, hospitalized during 3 waves (pre-Delta, Delta and Omicron) in Poland. Demographic and clinical information and neurological manifestations were collected and compared across three periods. Results: The median age of the study group was 68, lower during the Delta wave. In the Omicron period, the disease severity at admission and inflammatory markers concentration were the lowest. Neurological manifestations were observed in 49%. The most common were altered mentation, headache, myalgia, mood disorder, ischemic stroke and encephalopathy. Smell and taste disturbances (STDs) were less frequent in the Omicron period. Neurological complications were predominant in the pre-Delta and Omicron periods. Ischemic stroke was observed more often in pre-Delta period. Altered mentation was related to higher severity at admission, worse lab test results, higher admission to ICU and mortality, while headache reduced mortality. Pre-existing dementia was related to higher mortality. Conclusions: Neurological manifestations of COVID-19 are frequent, with a lower rate of STDs in the Omicron period and more often cerebrovascular diseases in the pre-Delta period. Headache improves the course of COVID-19, while altered mentation, stroke and neurological comorbidities increase severity and mortality.

Background: Severe traumatic brain injury (TBI) remains associated with high in-hospital mortality. Although classical clinical predictors are widely used, additional biomarkers reflecting systemic dysfunction may improve prognostic assessment. Small intestinal bacterial overgrowth (SIBO) may represent a late marker of critical illness. This study evaluated the prognostic value of SIBO compared with traditional predic-tors in severe TBI. Methods: In this retrospective cohort study, 174 patients with severe TBI (Glasgow Coma Scale ≤ 8) were included. Baseline clinical parameters were rec-orded at admission. Quantitative cultures of small intestinal aspirates were obtained at admission (colony-forming units per milliliter, CFU/mL; CFU1) and on days 12–14 (CFU14). Multivariable logistic regression, receiver operating characteristic (ROC), and landmark analyses were performed. Results: Age (OR 1.06 per year, 95% CI 1.03–1.10, p < 0.001), lower GCS (OR 0.48 per point, 95% CI 0.28–0.83, p = 0.008), and res-piratory dysfunction reflected by lower PaO₂/FiO₂ values independently predicted mortality. Late bacterial load >10⁵ CFU/mL showed a strong association with death (OR 5.15, 95% CI 2.15–12.34, p < 0.001). Baseline CFU1 was not significant. The model demonstrated good discrimination (AUC = 0.84). Landmark analysis confirmed higher post-day-14 mortality and delayed discharge with elevated CFU14. Conclusions: Late intestinal bacterial overgrowth is independently associated with mortality and may complement traditional predictors for risk stratification in severe TBI.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with neurological complications, like various autoimmune encephalitis (AE) types. This study aimed to identify and analyze COVID-19 cases diagnosed with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis (anti-NMDARE). Materials & Methods: This research summarized all post-pandemic reports. The review was conducted based on PRISMA ...