Reversible brain lesion following growth hormone replacement therapy in an adolescent

A 12.6-year-old girl presented with a 2-month history of headache, recurrent vomiting and 5 kg weight loss. She had been receiving recombinant human growth hormone (rhGH) replacement therapy at a dose of 0.035 mg/kg for the past 10 months, due to short stature. Investigations before initiating rhGH, including brain MRI, had been normal. Physical examination revealed a nystagmus and a mildly elevated arterial blood pressure. Brain MRI revealed a lesion in the posterior aspect of the medulla oblongata, adjacent to the foramen of Magendie. rhGH therapy was discontinued, followed by a gradual resolution of the symptoms. At follow-up 3 months later, she was asymptomatic and physical examination was unremarkable. A subsequent repeat brain MRI showed complete resolution of the lesion, supporting the diagnosis of a variant of reversible posterior leucoencephalopathy syndrome. This is the first case report of a reversible brain lesion linked to rhGH replacement therapy.