Case Report: Coinfection of Leprosy and Chronic Mucocutaneous Candidiasis in a Family with STAT1 Gain-of-Function Mutation.

This report documents the first known cases of lepromatous leprosy in patients with chronic mucocutaneous candidiasis (CMC) linked to a gain-of-function mutation in the STAT1 gene. Two related patients, a mother and daughter, who both suffer from CMC and lepromatous leprosy, carry a heterozygous STAT1 mutation (c.821G>A; p.R274Q). Both individuals exhibited similarly high levels of total and phosphorylated STAT1 in CD4+ T cells and decreased interleukin 17A transcripts. This mutation underscores a complex relationship between genetic susceptibility to infections and the necessity to evaluate each case individually.