Clinical and MRI characteristics of acute encephalopathy in congenital adrenal hyperplasia

Acute encephalopathy in childhood is frequently associated with common infections, especially in East Asia. Various types have been identified although many cases remain unclassified. Congenital adrenal hyperplasia (CAH) is an autosomal recessive disease presenting impairment of cortisol biosynthesis. We report three CAH children with acute infection-related encephalopathy. They exhibited disturbed consciousness or seizures, which did not improve after glucocorticoid administration, accompanied by clinical and laboratory findings of adrenal insufficiency. Brain MRI disclosed various patterns of white matter lesions, suggesting different types of acute encephalopathy such as clinically mild encephalitis/encephalopathy with a reversible splenial lesion or hemiconvulsion-hemiplegia syndrome. Acute encephalopathy should be considered and brain MRI immediately performed when impairment of consciousness does not improve after intravenous glucocorticoid administration in CAH patients. Further research is required to elucidate the epidemiology and pathogenic mechanisms of acute encephalopathy in CAH.