Karsch-Neugebauer syndrome

Karsch-Neugebauer syndrome is an extremely rare genetic disorder characterized by the combination of split hand/split foot malformation (ectrodactyly) and congenital nystagmus (involuntary rhythmic eye movements present from birth). The condition primarily affects the limbs and the ocular system. Split hand/split foot malformation involves a deep median cleft in the hands and/or feet, with absence or malformation of the central digits, giving a characteristic lobster claw-like appearance. The nystagmus can impair visual acuity and may be associated with other ocular findings. The syndrome was first described by Karsch in 1936 and further delineated by Neugebauer in 1962 based on observations in affected families. The syndrome follows an autosomal dominant inheritance pattern with variable expressivity, meaning that affected individuals within the same family may show different degrees of limb and eye involvement. The condition is present from birth, with limb malformations and nystagmus both being congenital features. There is no specific cure for Karsch-Neugebauer syndrome. Management is supportive and multidisciplinary, involving orthopedic interventions or reconstructive surgery for hand and foot malformations to improve function, as well as ophthalmologic care for nystagmus, which may include corrective lenses, prisms, or in select cases surgical procedures to reduce the nystagmus and improve visual function. Genetic counseling is recommended for affected families.

Common questions about Karsch-Neugebauer syndrome