Current infectious disease management challenges in inborn errors of immunity.

Inborn errors of immunity (IEIs) are a frequently underdiagnosed group of disorders, with infectious complications posing significant clinical challenges. Recognizing atypical presentations of common infections and the presence of rare opportunistic pathogens can be critical in suspecting an underlying IEI. Among the infectious complications, chronic viral infections are particularly difficult to manage due to limited evidence-based guidelines. Intra-host viral evolution in these patients can lead to treatment resistance and the emergence of novel viral strains, raising concerns about their potential role as reservoirs for mutant viruses. Novel pathogens such as Aichivirus have been identified as significant causes of infection in individuals with IEIs. Furthermore, infections such as talaromycosis, tuberculosis, BCG-related disease, leishmaniasis, and melioidosis may be underrecognized in certain groups of patients with IEIs, largely due to differences in geographic exposure and environmental risk factors. The effects of emerging infections, such as mpox and Middle East respiratory syndrome coronavirus, on individuals with IEIs remain largely unknown. Management strategies for infections in this population include vaccinations, immunoglobulin replacement, and antimicrobial prophylaxis. However, newer higher valency conjugate pneumococcal vaccines may limit the utility of traditional pneumococcal polysaccharide vaccines in assessing immune function. While immunoglobulin replacement is cost-effective, it can interfere with serological diagnostics. Additionally, antimicrobial resistance is a growing issue, emphasizing the need for improved empiric antibiotic strategies and research into optimal treatment durations. This review highlights the key challenges faced by infectious disease clinicians in the care of patients with IEIs.