Common Variable Immunodeficiency: Epidemiology, Pathogenesis, Clinical Manifestations, Diagnosis, Classification, and Management.

Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by hypogammaglobulinemia and increased susceptibility to recurrent bacterial infections. It is the most frequent symptomatic antibody deficiency, with a wide variety of infectious and noninfectious complications. Numerous studies have demonstrated that immunological and genetic defects are involved in the pathogenesis of CVID. However, in most cases, the genetic background of the disease remains unidentified. This review aims to discuss various aspects of CVID, including epidemiology, pathogenesis, symptoms, diagnosis, classification, and management.

Common variable immunodeficiency: epidemiology, pathogenesis, clinical manifestations, diagnosis, classification, and management

Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by hypogammaglobulinemia and increased susceptibility to recurrent bacterial infections. It is the most frequent symptomatic antibody deficiency, with a wide variety of infectious and noninfectious complications. Numerous studies have demonstrated that immunological and genetic defects are involved in the pathogenesis of CVID. However, in most cases, the genetic background of the disease remains unidentified. This review aims to discuss various aspects of CVID, including epidemiology, pathogenesis, symptoms, diagnosis, classification, and management

La inmunodeficiencia variable común (CVID) es un trastorno heterogéneo caracterizado por una hipogammaglobulinemia y por una mayor susceptibilidad a infecciones bacterianas recurrentes. Se trata de la inmunodeficiencia humoral sintomática más frecuente y cursa con una extensa variedad de complicaciones infecciosas y no infecciosas. En la patogenia de la CVID están involucrados diferentes defectos inmunológicos y genéticos. Sin embargo, en la mayoría de los casos, el fondo genético de la enfermedad permanece sin identificar. Esta revisión tiene como objetivo discutir diferentes aspectos de la CVID, incluyendo epidemiología, patogenia, síntomas, diagnóstico, clasificaciones y tratamiento de la enfermedad

Infectious etiology of chronic diarrhea in patients with primary immunodeficiency diseases.

Summary: Background.Primary immunodeficiency diseases (PIDs) are life-threatening disorders, which manifest commonly with gastrointestinal (GI) signs, mainly as chronic diarrhea. Objective. To investigate and compare infectious etiology of chronic diarrhea in different PIDs. Patients and methods. Assessing clinical features, obtaining immunological profiles, as well as characterizing infectious etiology of diarrhea were performed in 38 PID patients with chronic diarrhea. Stool samples and/or biopsy specimens were checked using culture, microscopic examination, RT-PCR, and PCR, as appropriate. The patients were diagnosed to have common variable immunodeficiency (CVID), severe combined immunodeficiency (SCID), X-linked agammaglobulinemia (XLA), and hyper-IgM (HIgM) syndrome. Results. In 32 patients we identified 41 infectious agents including 16 parasitic (39.0%, the most common Giardia lamblia), 11 bacterial (26.8%, the most common salmonella spp), 8 viral (19.5%, the most frequent group A rotavirus), and 6 fungal organisms (14.7%, the most common Candida albicans). From 6 of the patients, no infectious agent was isolated. In CVID bacteria and parasites, in SCID bacteria and viruses, in XLA parasites, and in individuals with HIgM syndrome parasites were the leading causes of chronic diarrhea. Infection with giardia and cryptosporidium were more frequent in XLA and HIgM, respectively. Conclusion. The current study suggests considering both usual and unusual pathogens in laboratory investigation and in the empiric treatment of chronic diarrhea. Opportunistic pathogens should be taken into account when no other pathogen is identified, especially in patients on long-term treatment or prophylaxis with antifungals/antibiotics and in those from geographical locations that favor pathogenicity of these organisms.

Rheumatologic complications in a cohort of 227 patients with common variable immunodeficiency.

Common variable immunodeficiency (CVID) is the most prevalent symptomatic type of human primary immunodeficiency diseases (PID). Clinically, CVID is characterized by increased susceptibility to infections and a wide variety of autoimmune and rheumatologic disorders. All patients with CVID registered in Iranian PID Registry (IPIDR) were enrolled in this retrospective cohort study. We investigated the frequency of rheumatologic diseases and its association with immunological and clinical phenotypes in patients with CVID. A total of 227 patients with CVID were enrolled in this study. The prevalence of rheumatologic disorders was 10.1% with a higher frequency in women than men. Most common rheumatologic manifestations were juvenile idiopathic arthritis (JIA) and adult rheumatoid arthritis (RA) followed by juvenile spondyloarthritis (JSpA) and undifferentiated inflammatory arthritis (UIA). Septic arthritis in patients with CVID with a history of RA and JIA was higher than patients without rheumatologic complication. Patients with CVID with a history of autoimmunity (both rheumatologic and non-rheumatologic autoimmunity) had lower regulatory T cells counts in comparison with patients without autoimmune disorders. There was an association between defect in specific antibody responses and negative serologic test results in patients with rheumatologic manifestations. JIA, RA, JSpA and UIA are the most frequent rheumatologic disorders in patients with CVID. Due to antibody deficiency, serologic tests may be negative in these patients. Therefore, these conditions pose significant diagnostic and therapeutic challenges for immunologists and rheumatologists in charge of the care for these patients.