Hypomelanosis of Ito associated with West syndrome: report of a case

Hypomelanosis of Ito (HI) is a rare neurocutaneous disorder characterized by hypopigmented macules along the Blaschko line and multiple abnormalities, including seizures, developmental retardation, ophthalmologic defects, and chromosome mosaicism. We report a four-month-old female baby with typical skin lesions on the right upper limb, chest, and scalp, noted at the age of one week. She also had a seizure disorder which manifested as neck flexion and hand gripping with series formation from the age of three months. Electroencephalogram (EEG) demonstrated modified hypsarrhythmia. The characteristic clinical and electroencephalographic features favored the diagnosis of West syndrome. Magnetic resonance imaging revealed an absence of abnormal neuronal migration. The auditory brainstem evoked response, nerve conduction velocity, and ophthalmologic examinations were all within normal limits. The seizure responded to adrenocorticotropic hormone therapy on the 12th day of initial therapy, and the EEG became normal. However, another different pattern of seizures characterized by staring and lateral gaze in a right upward direction occurred two weeks later. Carbamazepine and phenobarbital were added to the therapeutic regimen. She was regularly followed up at the outpatient department every two weeks after one-and-a-half months of hospitalization. Infantile spasms with evidence of hypsarrhythmias in the EEG recurred at seven months of age. Oral steroid therapy reduced seizure frequency by 80%. As far as we know, this is the first case report of HI combined with infantile spasms in Taiwan.