[Incontinentia pigmenti. Four patients with different clinical manifestations].

Incontinentia pigmenti (IP) is a rare neurocutaneous disorder with a frequency of 1 in 50,000 newborn, and is associated with mutations in IKBKG gene (NEMO) in Xq28, inherited as an X-linked dominant trait. Clinical manifestations detected since the newborn period are highly variable, with 3 well established sequential or overlapped states and each with a characteristic differential diagnosis. With PCR+RFLPs, we analyzed the IKBKG gene in 4 patients with different clinical manifestations and characteristic skin biopsy. In all 4 patients the same deletion of exons 4 to 10 was identified. In female patients in whom the dermatological lesions lead to the suspicion of an IP diagnosis, it is important to have the complete, multidisciplinary and molecular analysis of their first level female relatives. This should give us a clear diagnosis, which is the first step to complete genetic counselling.