Incontinentia pigmenti in an XY boy: case report and review of the literature.

BACKGROUND: Incontinentia pigmenti (IP) is a rare genetic skin disorder with X-linked dominant inheritance and a characteristic sequence of cutaneous manifestations, which is regarded as lethal in XY males.

OBJECTIVE: To report a case of a surviving XY male with the common IKBKG (NEMO) gene deletion confirming IP.

METHODS AND RESULTS: A newborn XY male with suspected IP underwent a skin biopsy on affected tissue for histopathology. Molecular genetic testing was also performed on the specimen and revealed the common IKBKG gene deletion with a pattern suggestive of somatic mosaicism. Our findings are aligned with a PubMed literature review for XY males with IP and documented IKBKG mutation. We determined that only 10 such genetically proven cases have been reported, including our case.

CONCLUSION: Although relatively rare, cases of IP in XY males with the common NEMO mutation have likely been underreported due to the unavailability of appropriate testing in the past. Karyotype and molecular testing should be considered when clinical suspicion of IP arises for a male patient.