Cerebral histiocytosis-x with endocrine symptoms.

A neuropathologically verified case of histiocytosis-X in a 21-year-old man with endocrine symptoms is presented. The granulomas were confined to the central nervous system and occupied mainly the pituitary stalk and hypothalamus, thus giving us the opportunity to observe the endocrine symptoms caused by such localized lesions. Diabetes insipidus was one cardinal endocrine symptom and is considered to be caused by a hypothalamic lesion in the supraoptic nuclei or the pathways to the posterior pituitary. In this case the anterior pituitary was not involved by granulomas, but the posterior lobe was atrophic. Severe hypogonadism and probably also a growth hormone defect were present, probably resulting from pituitary insufficiency secondary to the hypothalamic lesions. Hypothyroidism was another symptom but in this case was probably due to thyroiditis. Such a finding has previously been observed by two other authors and may therefore be pathologically connected to histiocytosis-X even though no granulomas were present in the thyroid gland. Repeated X-ray investigations from 9 years of age showed that the development of the sella turcica ceased about the same time as the patient got signs of diabetes insipidus. Increase in sellar volume normally reflects pituitary growth. The lesions in the pituitary stalk or the hypothalamus must therefore have been present from the time when diabetes insipidus started.