A 6-year-old boy came for MRI with complaints of delayed development, hypotonia, seizures.
Birth history was normal and he was born to non-consanguineous parents. His younger sibling was normal.
On clinical examination, the patient had multiple hypopigmented and hyperpigmented patches on limbs, back and chest.
Magnetic resonance imaging (MRI) of the brain showed T2W and FLAIR hyperintensities in deep periventricular white matter.
Multiple small T2W hyperintense cysts were seen within this affected deep periventricular white matter attenuating on FLAIR images.
The cysts were hypointense on T1W images.
Hypomelanosis of Ito (HMI) is also called incontinentia pigmenti achromians (IPA). It is a neurocutaneous syndrome, first described in medical literature in 1952. The aetiology is unknown in many cases associated with genetic mosaicism. Abnormalities are seen in chromosome 9q33, chromosome 15q11-q13, chromosome Xp11, Xp21.2, Xq28 . Hypomelanosis of Ito affects women more often than men, with an estimated incidence of 1 in 8000-10000 live births.
Hypomelanosis of Ito shows a wide spectrum of cutaneous and extra-cutaneous manifestations .
Cutaneous features, commonly seen, are hypopigmented patches, streaks, whorls involving any part of the body. A spectrum of extra-cutaneous neurological manifestations are seen like delayed development , seizures, hypotonia and microcephaly .
Orbitofacial abnormalities are cleft palate, cleft lip, dental abnormalities, microphthalmia  and strabismus.
Vertebral anomalies include kyphoscoliosis, limb anomalies include hemihypertrophy, with some cases showing renal and cardiac anomalies .
Patients should be investigated thoroughly with clinical evaluation, radiological imaging, and chromosomal studies for the diagnosis of this complex syndrome.
MRI is the choice of imaging modality to evaluate neurological structural abnormalities seen in this syndrome. Lesions are typically seen in periventricular white matter. MRI shows hyperintensities in deep periventricular white matter on T2W and FLAIR images, suggestive of defective myelination. Multiple small hyperintense cysts are seen on T2W images within affected periventricular white matter which are suggestive of dilated Virchow Robin spaces .
Migrational abnormalities are seen in some cases.
Depending on the spectrum of cutaneous and neuroradiological findings, diagnosis of hypomelanosis of Ito was made.
Treatment for hypomelanosis of Ito is symptomatic depending on cutaneous and extra-cutaneous features. It requires a team consisting of a neurologist, paediatrician, orthopaedist, dermatologist, ophthalmologist, urologist, cardiologist and dental specialist.
Skin lesions are managed conservatively.
Anticonvulsants are used to treat seizures.
Genetic counselling may be of benefit for the patients and their family.
This child presented with skin lesions, delayed development, seizures and hypotonia which was managed conservatively.
Hypomelanosis of Ito is not a life-threatening condition, but the intracranial manifestation, however, is permanent. The extra-cutaneous disease pattern is increasing in affected individuals. The most common cutaneous feature that is hypopigmentation may be misinterpreted as normal skin and adjacent normal skin interpreted as hyperpigmentation. This may impose difficulty in diagnosing this syndrome, which may be labelled as a different neurocutaneous syndrome or skin disease. Therefore symptomatic imaging is necessary for the diagnosis of this complex syndrome.
Differential Diagnosis List
Hypomelanosis of Ito