Candidiasis, familial, 6 B37.-

Chronic mucocutaneous candidiasis, familial type 6 (Candidiasis, familial 6) is a very rare, primary immunodeficiency disorder with impaired immune responses to fungal infections, selectively against Candida. The disease is characterized by persistent and/or recurrent infections of the skin, nails and mucous membranes caused by organisms of the Candida genus (mainly Candida albicans). The cause is a mutation in the IL17F gene.

Members of the interleukin-17 (IL-17) family as well as interleukin-22 (IL-22) are cytokines produced by type 17 lymphocytes. Both cytokines mediate antifungal immunity. They act synergistically but activate quite different downstream signaling pathways (Aggor FEY et al. 2020).

Puel et al (2011) discovered a heterozygous mutation of Ser65 to Leu in the IL17 gene. Serine-65 is conserved in all mammalian species. This mutation was found in all affected individuals, but also in two apparently healthy females at 9 months and 21 years of age.

1. Aggor FEY et al (2020) Oral epithelial IL-22/STAT3 signaling licenses IL-17-mediated immunity to oral mucosal candidiasis. Sci Immunol 5(48):eaba0570.
2. Puel A et al. (2011) Chronic mucocutaneous candidiasis in humans with inborn errors of interleukin-17 immunity. Science 332: 65-68.