A. Tan , S. Vaidya
Hypomelanosis of Ito (HMI) is a rare neurocutaneous condition
that is characterized by hypopigmented swirls and
streaks distributed along the lines of Blaschko. It was first
reported in the literature in 1952 and described as incontinentia pigmenti acrhomians.
It is believed that HMIis a result of chromosomal mosaicism and that a wide rangeof mutations can lead to the various phenotypic mosaic patterns seen in dyspigmentation of Blaschkoid distribution.
HMI typically presents at birth and can involve anywhere
on the cutaneous surface of the body. HMI has been
associated with highly variable extracutaneous abnormalities
affecting the neurological, musculoskeletal and ophthalmological
systems.
We present a 12-year-old Australian dark-skinned male who
presented with hypopigmented macules involving the left
side of his torso as well as his upper extremities since birth.
Both the patient and his parents denied any visual or neurological
symptoms. He had no developmental delay and no
family history involving this similar skin condition. This
young boy was reported to be generally fit and well with no
significant past medical history. On examination, he had
multiple ill-defined hypopigmented macules distributed
along the lines of Blaschko on the left side of his anterior
chest, upper shoulder, both upper arms and upper back. A
sharp midline cut-off was noted at the pre-sternal level.
There were no abnormalities involving his nails, eyes and
joints. His typical clinical presentation was most consistent
with a diagnosis of HMI.