Virus-specific humoral immune response in Bulgarian COVID-19 patients with varying disease severity.

Introduction: Our study aimed to analyze virus-specific humoral immune responses in COVID-19 patients with varying disease severity.

Methodology: A total of 109 serum samples from 87 patients, symptomatic for COVID-19 were studied using anti-SARS-CoV-2 immunoassays detecting different classes of immunoglobulins.

Results: Clinical samples were divided into 2 groups - collected up to and more than 2 weeks post-onset of symptoms (PoS).

Mild to moderate clinical course of COVID-19 infection in patients with common variable immune deficiency.

The association of immunocompromised patients and severity of COVID-19 infection is not well established. According to the Centers for Disease Control and Prevention (CDC), primary immune deficiencies (PIDs) are among the conditions that can predispose to a more severe course of COVID-19. We report the clinical course and immunological evaluation of five patients with common variable immune deficiency (CVID) who have experienced SARS-CoV-2 virus.

Vasculitis as a Major Morbidity Factor in Patients With Partial RAG Deficiency.

Vasculitis can be a life-threatening complication associated with high mortality and morbidity among patients with primary immunodeficiencies (PIDs), including variants of severe and combined immunodeficiencies ((S)CID). Our understanding of vasculitis in partial defects in recombination activating gene (RAG) deficiency, a prototype of (S)CIDs, is limited with no published systematic evaluation of diagnostic and therapeutic modalities. In this report, we sought to establish the clinical, laboratory features, and treatment outcome of patients with vasculitis due to partial RAG deficiency.

Chronic hepatitis C virus infection: prevalence of extrahepatic manifestations and association with cryoglobulinemia in Bulgarian patients.

Aim: To assess the prevalence of extrahepatic manifestations in Bulgarian patients with chronic hepatitis C virus (HCV) infection and identify the clinical and biological manifestations associated with cryoglobulinemia.

Methods: The medical records of 136 chronically infected HCV patients were reviewed to assess the prevalence of extrahepatic manifestations. Association between cryoglobulin-positivity and other manifestations were identified using chi2 and Fisher's exact test.