Patient 3, a 10-year-old boy, was born by normal delivery. His parents did not show cutaneous anomalies. He was admitted for consultation due to episodes of generalized tonic-clonic seizures lasting several minutes: seizures had started at age 2 years. He showed neurodevelopmental delay from his first months of life: his current school performance is poor. An electroencephalographic (EEG) examination revealed spike and wave discharges in the temporal and parietal regions. Treatment with sodium valproate substantially reduced the frequency of seizures. At physical examination, he weighted 34 kg, with a height of 141 cm (75th percentile). The hypopigmented lesions were localized in the thorax and in the back, mainly on the left side. The diameter of the sural region of the lower left limb was 8 cm larger than the contralateral, and the diameter of the biceps region of the left limb was 3 cm larger than the contralateral. The left lower limb was 2 cm longer than the right. The asymmetry involved also the left hemiface. A lower-limb MRI showed increased growth in both long bones and soft tissues. Mild thoracolumbar right kyphoscoliosis was noticed. Brain MRI and ophthalmologic examination were both normal.
A 5.5-year-old girl was brought to our hospital with a complaint of disproportionate overgrowth and lengthening of the right leg accompanied by marked hypopigmented lesions over the trunk and legs, which reportedly had become noticeable by 2-weeks postpartum and gradually increased and spread. She was born to non-consanguineous parents and had been under monitoring for delayed speech. On examination, her height and weight were 110 cm (10th to 25th percentile) and 23 kg (75th to 90th percentile), respectively. The dermatological examination was remarkable for hypopigmented patches following the Blaschko lines over the trunk and both legs, more prominently on the right leg (, ), which was thicker and longer (~2 cm) than the left (). Apart from these findings, the systemic examinations, routine haemogram and biochemical tests, and magnetic resonance scans of the cranium and lower extremities were normal. When the Denver Developmental Screening Test was administered for speech delay, it was graded as ‘delayed’, correlating with the age of 3.5 years. After consultation with the dermatology department, a skin biopsy was considered unnecessary.