Viral infections and inborn errors of immunity.

Purpose of review: The purpose of this focused review is to discuss unusual presentations of viral infections in the context of specific inborn errors of immunity. We will discuss hyper immunoglobulin E (IgE) syndromes, epidermodysplasia verruciformis, and X-linked agammaglobulinemia as examples of inborn errors of immunity associated with specific presentations of viral infection and disease.

Recent findings: Advances in both genetic and viral diagnostics have broadened our understanding of viral pathogenesis in the setting of immune dysfunction and the variable phenotype of inborn errors of immunity. Dedicator of cytokinesis 8 (DOCK8) deficiency is now recognized as an inborn error of immunity within the hyper IgE syndrome phenotype and is associated with unusually aggressive cutaneous disease caused by herpes simplex and other viruses. Studies of patients with epidermodysplasia verruciformis have proven that rarely detected human papillomavirus subtypes may cause malignancy in the absence of adequate host defenses. Finally, patients with X-linked agammaglobulinemia may remain at risk for severe and chronic viral infections, even as immune globulin supplementation reduces the risk of bacterial infection.

Summary: Susceptibility to viral infections in patients with inborn errors of immunity is conferred by specific, molecular defects. Recurrent, severe, or otherwise unusual presentations of viral disease should prompt investigation for an underlying genetic defect.