Diabetes insipidus and histiocytosis X: a case of isolated pituitary involvement.

Diabetes insipidus is associated with histiocytosis X in approximately 50% of cases with multiple lesions that involve both intracranial and extracranial structures. Although approximately 8% of cases of diabetes insipidus in children are caused by involvement of the hypothalamus or pituitary infundibulum (or both) by histiocytosis X, diabetes insipidus can be the initial manifestation in many disorders most commonly, intracranial neoplasms. Herein we report a case of isolated histiocytosis X of the pituitary gland in a child for whom medical assistance was sought because of symptoms of diabetes insipidus.