A case of lymphocytic infundibuloneurohypophysitis showing diabetes insipidus followed by anterior hypopituitarism associated with thrombasthenia

We report a case of a 42-year old male patient with diabetes insipidus foll owed by anterior hypopituitarism associated with thrombasthenia. The patien t had been diagnosed with thrombasthenia since the age of 19. He was admitt ed and diagnosed as diabetes insipidus in 1995. Although T1-weighted image of magnetic resonance imaging (MRI) showed empty sella and partial pituitar y stalk hypertrophy, the anterior pituitary functions were normal at that t ime. Three years later, he was re-admitted after an episode of general mala ise and impotence in 1998. Endocrinological studies revealed adrenal insuff iciency, hypothyroidism and hypogonadism. T1-weighted image of MRI demonstr ated the thickening of pituitary stalk and neurohypophysis. Analysis of ant i-pituitary antibodies by immunoblotting identified a major band at 61.5 kD a. The diabetes insipidus was controlled by desmopressin acetate and the sh rinkage of pituitary stalk was seen, after hormonal replacement therapy inc luding glucocorticoid and thyroid hormone. We suggested that this case repr esented lymphocytic infundibuloneurohypophysitis, in which a chronic inflam matory process occurred in infundibulum and/or neurohypophysis and that hyp opituitarism developed possibly due to damage to the pituitary portal vesse ls caused by a thickened pituitary stalk, although a pituitary biopsy was n ot done because of the risk of bleeding in thrombasthenia. The pituitary au toantibodies in sera from patients with hypopituitarism may be helpful to c haracterize the patient with lymphocytic hypophysitis.