[Incontinentia pigmenti in a male patient].

Incontinentia pigmenti (Bloch-Sulzberger syndrome) is a rare genetic disorder usually affecting females. Familial cases show an X-linked dominant inheritance with male lethality. The typical skin manifestations occur in several stages and can be associated with various extracutaneous anomalies. We report on a 10-month-old male patient with incontinentia pigmenti (IP) and a normal male karyotype. Besides the typical cutaneous lesions no other signs have been found so far. IP in male patients can be explained by the presence of Klinefelter syndrome, by the half-chromatid mutation model, or by an early somatic mutation. On the basis of this case report we discuss the clinical findings in and the genetics of IP.