Four-year follow-up of megalencephaly, polymicrogyria, postaxial polydactyly and hydrocephalus (MPPH) syndrome.

A male infant was born by emergent caesarean section at 39 weeks gestational age secondary to maternal and fetal distress. Initial physical examination was notable for macrocephaly (greater than+2SD), postaxial polydactyly of the hands and facial dysmorphism. Head imaging demonstrated diffuse polymicrogyria without hydrocephalus. All findings were consistent with a diagnosis of megalencephaly, polymicrogyria, postaxial polydactyly and hydrocephalus (MPPH) syndrome. At the 4-year follow-up, megalencephaly persisted without evidence of hydrocephalus. The child was severely delayed with a stable seizure disorder controlled with dual antiepileptic therapy. This case meets the classic criteria for MPPH syndrome, adding to the limited experience with this disease. The 4-year follow-up and absence of hydrocephalus, once thought to be a key diagnostic criterion, adds to our understanding of the long-term sequelae.