• Anterior Hypopituitarism is Rare and Autoimmune Disease is Common in Adults with Idiopathic Central Diabetes Insipidus.

      Academic Department of Endocrinology, Beaumont Hospital / RCSI Medical School,, Dublin 9, Ireland And Endocrine Unit, Royal Victoria Infirmary, Newcastle, Hospitals NHS Trust and University of Newcastle, Newcastle-Upon-Tyne, NE1 4LP,, United Kingdom. (2012-02-01)
      Objective: Central diabetes insipidus is a rare clinical condition with a heterogenous aetiology. Up to 40% of cases are classified as idiopathic, though many of these are thought to have an autoimmune basis. Published data has suggested that anterior hypopituitarism is common in childhood onset idiopathic diabetes insipidus. We aimed to assess the incidence of anterior hypopituitarism in a cohort of adult patients with idiopathic diabetes insipidus. Design and Patients: We performed a retrospective review of the databases of two pituitary investigation units. This identified 39 patients with idiopathic diabetes insipidus. All had undergone MRI scanning and dynamic pituitary testing (either insulin tolerance testing or GHRH/arginine and short synacthen testing) to assess anterior pituitary function. Results: One patient had partial growth hormone deficiency; no other anterior pituitary hormonal deficits were found. 33% had at least one autoimmune disease in addition to central diabetes insipidus. Conclusions: Our data suggest that anterior hypopituitarism is rare in adult idiopathic diabetes insipidus. Routine screening of these patients for anterior hypopituitarism may not therefore be indicated. The significant prevalence of autoimmune disease in this cohort supports the hypothesis that idiopathic diabetes insipidus may have an autoimmune aetiology.