Clinical features and mental development of a child with a prenatally identified 45,XX,der(5)t(5;18) (p15;q11.2),-18 karyotype.

We present the clinical features and growth and development of a child with a 45,XX,der(5)t(5;18) (p15;q11.2),-18 karyotype. She had microcephaly, prominent, posteriorly rotated ears, short palpebral fissures with an upward slant, a wide nasal bridge, a thin upper lip, and a short neck. In addition, she had complex congenital heart disease. Although there has been delay in growth and development, she has shown progress in both areas.