Incontinentia pigmenti (IP; MIM308310) is a rare neurocutaneous X-dominant inherited disorder. Besides skin and neurological abnormalities, there is also ophthalmologic and dental involvement. The first stage is characterised by inflammation and apoptosis of the skin and central nervous system. The first stage consists of vesicles and the second of verrucous elements; the third stage is characterised by hyperpigmentation while the fourth is characterised by slightly atrophic hypopigmentations. The skin abnormalities follow the lines of Blaschko. The disorder is observed almost exclusively in girls, but diseased boys are more seriously affected. The IP gene is localised on chromosome Xq28. Mutations in the NEMO-gene are responsible for IP. This gene codes for the nuclear factor-KB essential modulator protein (NEMO; synonym: inhibitor kappaB kinase (IKK)y). In the absence of serious neurological symptoms, the prognosis is not poor.