Lyme Neuroborreliosis in the Context of Dementia Syndromes.

Lyme disease (LD) can affect the skin, joints, heart, and nervous system as a multisystemic condition. The cause of the illness is the spirochete of the genus Borrelia. These pathogens can affect the skin, joints, heart, and nervous system. Lyme neuroborreliosis (LNB) is the term for the disease, which occurs when the nervous system gets involved. Regarding geographical distribution, LNB is more prevalent in Europe than in North America. The most significant change in pathogenesis is inflammation of the central nervous system (CNS) and peripheral nervous system (PNS). Furthermore, clinically, it can represent a variety of neurological manifestations, such as meningitis, encephalitis, radiculopathies, and cranial neuritis. However, dementia-like syndrome is an infrequent manifestation of Lyme disease. Our review article aims to summarize the similarities and differences between dementia-like syndrome in LNB and that in primary neurodegenerative diseases, as well as to look for a correlation between the pathogenesis of the disease and the possibility of developing dementia-like syndrome. The world literature lacks sufficiently convincing data on the relationship between spirochete infection and primary dementia syndromes. However, cases of secondary dementia syndrome due to nervous system involvement as well as post-treatment have been described. A thorough examination, medical history, laboratory and imaging studies, cerebrospinal fluid (CSF) examination, MRI, and fludeoxyglucose-18-positron emission tomography (FGD-PET) are required to differentiate between these syndromes.

Rare host variants in ciliary expressed genes contribute to COVID-19 severity in Bulgarian patients.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a pneumonia with extremely heterogeneous clinical presentation, ranging from asymptomatic to severely ill patients. Previous studies have reported links between the presence of host genetic variants and the outcome of the COVID-19 infection. In our study, we used whole exome sequencing in a cohort of 444 SARS-CoV-2 patients, admitted to hospital in the period October-2020-April-2022, to search for associations between rare pathogenic/potentially pathogenic variants and COVID-19 progression. We used gene prioritization-based analysis in genes that have been reported by host genetic studies. Although we did not identify correlation between the presence of rare pathogenic variants and COVID-19 outcome, in critically ill patients we detected known mutations in a number of genes associated with severe disease related to cardiovascular disease, primary ciliary dyskinesia, cystic fibrosis, DNA damage repair response, coagulation, primary immune disorder, hemoglobin subunit ß, and others. Additionally, we report 93 novel pathogenic variants found in severely infected patients who required intubation or died. A network analysis showed main component, consisting of 13 highly interconnected genes related to epithelial cilium. In conclusion, we have detected rare pathogenic host variants that may have influenced the COVID-19 outcome in Bulgarian patients.

Virus-Specific Stem Cell Memory CD8+ T Cells May Indicate a Long-Term Protection against Evolving SARS-CoV-2.

Immune memory to SARS-CoV-2 is key for establishing herd immunity and limiting the spread of the virus. The duration and qualities of T-cell-mediated protection in the settings of constantly evolving pathogens remain an open question. We conducted a cross-sectional study of SARS-CoV-2-specific CD4+ and CD8+ T-cell responses at several time points over 18 months (30-750 days) post mild/moderate infection with the aim to identify suitable methods and biomarkers for evaluation of long-term T-cell memory in peripheral blood. Included were 107 samples from 95 donors infected during the periods 03/2020-07/2021 and 09/2021-03/2022, coinciding with the prevalence of B.1.1.7 (alpha) and B.1.617.2 (delta) variants in Bulgaria. SARS-CoV-2-specific IFNγ+ T cells were measured in ELISpot in parallel with flow cytometry detection of AIM+ total and stem cell-like memory (TSCM) CD4+ and CD8+ T cells after in vitro stimulation with peptide pools corresponding to the original and delta variants. We show that, unlike IFNγ+ T cells, AIM+ virus-specific CD4+ and CD8+ TSCM are more adequate markers of T cell memory, even beyond 18 months post-infection. In the settings of circulating and evolving viruses, CD8+ TSCM is remarkably stable, back-differentiated into effectors, and delivers immediate protection, regardless of the initial priming strain.

Fever of unknown origin and Q-fever: a case series in a Bulgarian hospital.

BACKGROUND: Fever of unknown origin (FUO) is a perplexing medical problem. The causes for FUO are more than 200 diseases. The aim of the study was to present human clinical cases of Coxiella burnetii infection debuting as FUO. METHODS: The following methods were conducted in the study: literature search, laboratory, imaging, and statistical methods. Criteria of Durack and Street were applied for FUO definition. For the etiological diagnosis indirect immunoenzyme assay (ELISA) for antibodies detection against Coxiella burnetii was used (cut-off = 0.481-0.519). RESULTS: From 2008 until 2015, nine patients with FUO caused by C. burnetii were hospitalized at the Military Medical Academy of Sofia. Male gender was predominant (male/female - 77.8% /22.2%), mean age was 48.78±14.52 years (range: 26-67), hospital stay was 9.78±2.95 days (range: 5-15), fever duration was 54.33±56.23 days (range: 21-180). Laboratory investigations estimated the elevation of erythrocyte sedimentation rate 49.11±31.74mm/h (95%CI = 13.09-111.31), C-reactive protein 37.68±37.62mg/L (95% CI = 36.07-111.42) and fibrinogen 5.69±1.59g/L (95% CI=2.57-8.81). The mean values of liver enzymes were in reference range. Among imaging tests, abdominal ultrasound and X-ray demonstrated 33.3% contribution to the final diagnosis. Transthoracic echocardiography found 22.2% contribution. Serological methods presented 100% contribution. CONCLUSION: C. burnetii infection was accepted as a final diagnosis among 9 patients with FUO based on the integrated information from the applied methods. Active search and establishment of this pathogen among FUO should lead to avoiding potential complications and consequences in case of untreated patients infected with C. burnetii.