Human MALT1 deficiency and predisposition to infections.

Human germline MALT1 deficiency is an inborn error of immunity characterized by recurrent bacterial, viral, and fungal infections, periodontal disease, enteropathy, dermatitis, and failure to thrive. The number of identified MALT1-deficient patients have greatly increased in the past two years, which has significantly improved our understanding of the clinical features of this disorder. Patients frequently experience infections affecting the respiratory, skin, gastrointestinal, and blood systems. The most frequently detected pathogens are Staphylococcus aureus, Candida albicans, and cytomegalovirus. Enhanced susceptibility to S. aureus and C. albicans is likely due to impaired Th17 immunity, similar to STAT3 and IL-17 pathway deficiencies.