Infectious Complications Reporting in Common Variable Immunodeficiency: A Systematic Review and Meta-analysis

Area of Science:

• Immunology
• Clinical Medicine
• Infectious Diseases

Background:

• Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by hypogammaglobulinemia, leading to heightened susceptibility to infections.
• CVID is a heterogeneous condition with varied clinical presentations and underlying immunological defects.

Purpose of the Study:

• To investigate the prevalence of various infections in patients with Common variable immunodeficiency (CVID).
• To explore the relationship between lymphocyte subsets, immunoglobulin levels, and infectious complications in CVID patients.

Main Methods:

• A systematic literature search was conducted across PubMed, Web of Science, and Scopus databases up to January 2018.
• Random-effects models were employed to calculate pooled estimates of infection prevalence and their 95% confidence intervals.

Main Results:

• Pneumonia was the most common infection (67.7%), followed by upper respiratory (59.0%) and gastrointestinal infections (36.3%).
• Bacterial infections were more prevalent (41.7%) than viral (25.4%), parasitic (18.8%), or fungal (3.4%) infections.
• Specific lymphocyte subsets (CD3, CD4, CD8, CD19) and immunoglobulin levels (IgM, IgG) showed correlations with different types of infections and disease comorbidities.

Conclusions:

• Common variable immunodeficiency (CVID) is associated with not only hypogammaglobulinemia but also a significant imbalance in T lymphocyte frequencies.
• This T lymphocyte imbalance contributes to the high frequency of infectious complications observed in CVID patients.