Same Skin, Different Story: Exploring the Clinical Spectrum of Hypomelanosis of Ito in Two Paediatric Patients

Introduction
Hypomelanosis of Ito is a cutaneous mosaic disorder characterized by hypopigmented lesions along the lines of Blaschko. It may present as an isolated skin finding or be associated with multisystem abnormalities, classifying it as a neurocutaneous syndrome.

Objective
To present two paediatric cases of hypopigmentation distributed along the lines of Blaschko – one associated with multisystem involvement and the other limited to cutaneous findings.

Case report
The first case involved a 5-year-old boy with pigmentary mosaicism and multiple extracutaneous features, including developmental delay, chest wall deformity, and auditory and ophthalmologic anomalies, consistent with hypomelanosis of Ito. The second case, a 9-year-old boy, had similar cutaneous findings but no systemic involvement, consistent with cutaneous pigmentary mosaicism.

Conclusions
These cases highlight the spectrum of hypomelanosis of Ito and the importance of a thorough clinical evaluation. Recognizing extracutaneous manifestations is key to accurate diagnosis, appropriate follow-up, and interdisciplinary care.