Idiopathic hypothalamus-pituitary dysfunction: review of five cases

We describe 5 children, 4 girls, aged 4-14 years with evolving hypothalamic-pituitary dysfunction. They had presenting features, isolated or combined, of polyuria and polydipsia (n = 3), weight gain and hyperphagia (n = 3), and growth failure (n = 1). During periods of 1-5 years per child, the following abnormalities developed: diabetes insipidus (n = 5), osmoreceptor dysfunction (hypernatraemia with absent thirst) (n = 3), hyperprolactinaemia (n = 3), growth hormone (GH) deficiency (n = 4, of whom 3 had normal linear growth), ACTH deficiency (n = 2), TSH deficiency (n = 2) and precocious puberty (n = 1, female). In 2 patients, high-resolution CT scans and MRI showed structural lesions of the hypothalamus 1.5 and 3.5 years after presentation. These were inaccessible and not biopsied. Scans in the remainder were normal. In conclusion, weight gain, impaired thirst, and hyperprolactinaemia were early features of evolving hypothalamic-pituitary dysfunction, and occurred with diabetes insipidus, accompanied by progressive anterior pituitary deficiencies. Pituitary hormone replacement with clinical and neuroradiological surveillance is important in any child with symptoms suggestive of an evolving hypothalamic lesion.