Chronic mucocutaneous candidiasis with STAT1 gain-of-function mutation associated with herpes virus and mycobacterial infections

Introduction: Chronic mucocutaneous candidiasis (CMC) is characterized by susceptibility to chronic or recurrent infections with yeasts of the genus Candida affecting the skin, nails and mucous membranes. We describe a Moroccan patient presenting CMC with heterozygous STAT1 gain-of-function (GOF) mutation. Patients and methods: A 5-year-old boy with no consanguinity presented recurrent episodes of oral thrush, chronic nail candidiasis and herpetic gingivostomatitis from the age of 8 months. He also had mycobacterial adenitis secondary to BCG vaccination and atypical rosacea. Genetic analysis revealed GOF mutation of the STAT1 gene. Discussion: CMC was diagnosed in our patient despite poor clinical features. Sequencing of the genome revealed STAT1 GOF mutation. This mutation affects production of IL-17, an important cytokine in mucocutaneous defense against Candida. The association with mycobacterial adenitis is rare and continues to be poorly understood. The presence of atypical rosacea in this setting is suggestive of this entity. Antifungal therapy and prevention of complications are necessary to reduce the morbidity and mortality associated with this condition. Conclusion: CMC due to STAT1 GOF mutation is characterized by a broad clinical spectrum and should be considered in all cases of chronic or recurrent fungal infection, whether or not associated with other infections.