Incontinentia pigmenti in a male (XY) infant with long‐term follow up over 8 years

Incontinentia pigmenti (IP) is an X‐linked genodermatosis affecting the skin and other sites, including the teeth, nails, hair, eyes and nervous system defects in female patients. Generally lethal in males, there are only a few known cases of males surviving this condition. Nuclear factor (NF)‐κB essential modulator (NEMO), also known as inhibitor of kappa light polypeptide gene enhancer in B cells, kinase gamma (IKBKG), constitutes an essential activator of NF‐κB. Over 80% of female patients with IP carry a common deletion mutation involving exons 4–10 of the IKBKG/NEMO gene. We present the case of a male infant (XY) with IP with no concomitant complications. Polymerase chain reaction (PCR) assay showed that the exon 4–10 deletion band was significantly stronger in the skin sample than in blood. Subsequently, long‐range PCR was performed periodically to confirm the spontaneous regression of mutant cells from his blood. Over a period of 6 years, the 2.6‐kb mutant band gradually became weaker, but we did not confirm complete regression. Our patient was a healthy, 8‐year‐old male child with no complications despite the presence of a 2.6‐kb mutant band in his blood. Further follow up is necessary to assess for complications that may develop later.