Crouzon Syndrome with Acanthosis Nigricans: A Case Report

Crouzon Syndrome (CS) with Acanthosis Nigricans is a disorder characterised by the premature joining of certain bones of the skull {Craniosynostosis (CSO)} during development and a skin condition called Acanthosis Nigricans. Two cases of CSO with abnormal facies were referred to the present tertiary genetic centre. The first case was a one-year-three-month-old female with CSO, normal Intelligence Quotient (IQ) and normal limbs, clinically diagnosed as CS. The second case was a two-year-two-month-old male child with CSO, choanal atresia, hydrocephalus, normal limbs, post-surgical follow-up and suspected as a syndromic CSO. Both cases showed the presence of diffuse Acanthosis Nigricans and the final diagnosis was CS with Acanthosis Nigricans. This condition is distinct from classical CS due to its dermatological features, hydrocephalus, choanal atresia and impaired glucose values. CS with Acanthosis Nigricans (CAN) showed a specific mutation in the Fibroblast Growth Factor Receptor 3 (FGFR3) gene, while Classical CS, in contrast, has a mutation in the FGFR 2 gene. Both of these cases were confirmed by molecular testing as CAN. This is a very rare condition in our population because of its peculiar clinical associations.