Evolution of childhood central diabetes insipidus into panhypopituitarism with a large hypothalamic mass: is 'lymphocytic infundibuloneurohypophysitis' in children a different entity?

We report on a 15-year-old girl who had presented with acute onset central diabetes insipidus at the age of 8 years: this was followed by growth failu re due to acquired growth hormone deficiency. Initial magnetic resonance im aging showed a uniformly enlarged pituitary stalk and absence of posterior pituitary hyperintensity. Frequent patient examination and magnetic resonan ce imaging gave unchanged results until after 5 years a large hypothalamic mass and panhypopituitarism were found. Dynamic magnetic resonance imaging documented hypothalamic-pituitary vasculopathy. Histopathological examinati on revealed perivascular inflammatory lymphoplasmic infiltrates with no gra nulomatosis or necrosis and negative staining for S-100 protein, suggesting autoimmune-inflammatory disease (lymphocytic infundibuloneurohypophysitis! ). The response to glucocorticoid pulses (30 mg/kg per day for 3 days i.v.) was favorable, the hypothalamic mass being halved and partial anterior pit uitary function recovery maintained for 2 years after the start of treatmen t. Mie suggest that long-term surveillance is needed for isolated and chron ic thickening of the pituitary stalk and that dynamic magnetic resonance im aging can contribute to the demonstration of hypothalamic-pituitary vascula r impairment associated with local vasculitis.