“From Sheep to Babe” - Menkes Disease

Abstract

A four-month-old boy presented with a new onset focal seizure lasting 18 minutes. During the seizure, his head and eyes were deviated to the left, and he assumed a fencing posture to the left with pursing of his lips. He had been unwell for one week, with episodes of poor feeding, during which he would become unresponsive, limp and stare for a few seconds. Developmentally he was delayed. He was not yet rolling, and he had only just begun to lift his head in prone position. He could grasp but was not reaching or bringing his hands together at the midline. He was cooing but not laughing. His past medical history was significant for term delivery with fetal distress and meconium staining. He was flat and blue at birth, with birth weight of 3.5 kg, and Apgar scores of 1 at one minute, 4 at 5 minutes, and 8 at 10 minutes. He required resuscitation with positive pressure ventilation for two minutes, and then had no further postnatal complications. Family history was remarkable for a paternal cousin with cortical malformation, epilepsy, and developmental delay. His mother and maternal grandmother had migraine headaches and fibromyalgia.On examination, his length (66 cm) and head circumference (43 cm) were at the 50th percentile, and his weight (6.6 kg) was at the 75th percentile. He had short bristly pale hair, and a cherubic appearance with full cheeks. His skin was velvety and lax. He was hypotonic with significant head lag and slip-through on vertical suspension. His cranial nerves were intact. He moved all limbs equally well with normal strength. His deep tendon reflexes were 3+ at patellar and brachioradialis, and 2+ elsewhere. Plantar responses were upgoing.Laboratory investigations showed increased lactate (7.7 mmol/L) and alkaline phosphatase (505 U/L), with normal CBC, electrolytes, calcium, magnesium, phosphate, ammonia, and liver enzymes. A brain CT scan demonstrated diffuse atrophy of the cerebral hemispheres, initially attributed to perinatal hypoxic-ischemic insult. Subsequent brain MRI showed atrophy and impaired myelination, with abnormal hypointense T1 signal and hyperintense T2 signal in the white matter of both frontal and temporal lobes. Tortuous blood vessels could also be seen (Figure 1). His EEG was abnormal, with poorly organized