Iatrogenic Creutzfeldt–Jakob disease presenting 24 years after human growth hormone administration

Abstract

A 39-year-old, right-handed female presented to the neurology outpatient clinic with a 6-month history of progressive unsteadiness. Before this she had been walking normally, but over the previous 6 months she had had recurrent falls and was now only able to walk with the aid of support. Her husband had also noticed that for the past few months she had jerky upper limb movements in her sleep and on waking from sleep, suggestive of myoclonic jerks. She was also having episodes of forgetfulness, e.g. forgetting to turn off light. She did not have any personality change or hallucinations, nor did she have any visual disturbance or difficulty with speech or swallow. Her past medical history consisted of craniopharyngioma from the age of 6 years, which had been treated conservatively. From 12–18 years of age she had been receiving human growth hormone injections for short stature. Mini mental state examination was 28/30. The cranial nerves were all normal as was the motor system. She exhibited impaired coordination in all four limbs and walked with an ataxic gait. There was no obvious myoclonus on examination. Investigations revealed normal full blood count, renal and liver function tests. A magnetic resonance imaging (MRI) scan of her brain including fluid-attenuated inversion recovery (FLAIR) images showed increased signal in the caudate nuclei, and on diffusion images the caudate nuclei were hyperintense. There was increased signal adjacent to the aqueduct on T1 weighted imaging. Formal neuropsychological testing showed a mild to moderately severe impairment of shortterm memory. These findings of a cerebellar syndrome in a patient with a past history of human growth hormone injection and supporting MRI findings were consistent with a diagnosis of iatrogenic Creutzfeldt–Jakob disease.