Anorectal Malformations are Part of the Phenotypic Spectrum of Coffin-Siris Syndrome: Case Report and Review of the Literature

Anorectal malformations (ARMs) represent a wide spectrum of congenital anomalies of the anus and rectum, of which more than half are syndromic. Their etiology is highly heterogeneous and still poorly understood. We report a 4-year-old girl who initially presented with an isolated ARM, and subsequently developed a global developmental delay as part of an ARID1B-related Coffin-Siris syndrome (CSS). The co-occurrence of ARMs and CSS in an individual is unexpected since both disease are very rare. A review of the literature enabled us to identify 12 individuals with both CSS and ARMs. Among these 12 individuals, 9 had a variant in ARID1A, 2 in ARID1B, and 1 in SMARCA4. These data suggest a non-random association between CSS and ARMs, and indicate that ARMs is likely a rare feature of CSS.