Novel STAT1 mutation in a paediatric case of chronic mucocutaneous candidiasis complicated by primary hypothyroidism: clinical presentation, genetic analysis and prognostic implications.

This case report presents a young girl in her early childhood diagnosed with chronic mucocutaneous candidiasis (CMC) and primary hypothyroidism. Genetic analysis revealed a novel de novo mutation in the STAT1 gene (exon 11, c.972C>G, p.Cys324Trp), adding to the existing literature on STAT1 mutations, which account for approximately 53% of CMC cases. The identified mutation is predicted to have a more severe pathogenic impact based on PolyPhen-2 scoring. Our findings emphasise the importance of comprehensive genetic testing in CMC diagnosis and suggest that the specific mutation site may correlate with disease prognosis. The case underscores the need for vigilant monitoring and targeted therapeutic interventions, given the potential for poorer outcomes.