Incidence of pituitary autoantibodies in idiopathic diabetes insipidus

Abstract

Diabetes insipidus is a disorder resulting from insufficient action of vasopressin (ADH) characterized by excretion of highly diluted urine in large amounts. Idiopathic diabetes insipidus is associated with the presence of both autoantibodies against ADH-secreting neurons and pituitary autoantibodies. The aim of the present study was to evaluate the occurrence of autoantibodies against the pituitary microsomal fraction. The study included 33 sera of diabetes insipidus patients and 10 control sera obtained from 10 healthy persons. In all patients the secretion of pituitary hormones and thyroid autoantibodies was assessed. Human pituitaries were obtained during autopsy and homogenized in 0.01 mol/l pH 7.4 phosphate buffer. In addition, for the autoantibody evaluation, the electrophoretic method of separation in polyacrylamide gel and western blot were employed. Among the 33 subjects, in 23 patients the presence of autoantibodies against the pituitary was shown. Sera of 15 patients reacted with the pituitary microsomal fraction protein of 55 kDa. In other cases, 10 sera reacted with the pituitary antigen of 67 kDa. In addition, 5 sera reacted with the 60 kDa antigen, 5 sera with 52 kDa protein, 3 sera with 105 kDa protein, 3 sera with the 97 kDa antigen and 2 sera with pituitary antigen of 92 kDa weight. In our study, based on the immunoblotting method, we observed that pituitary autoantibodies against 55, 60 and 67 kDa antigens occurred frequently.

Pituitary Microsomal Autoantibodies in Patients with Childhood-Onset Combined Pituitary Hormone Deficiency: an Antigen Identification Attempt

“…These studies revealed reactivity against 58, 60, 67, 68 and 100 kDa antigens (Sawicka et al 1999). The other studies revealed the presence of M-APA in patients with Hashimoto thyroiditis (60 %), Graves’ disease (72 %), and Addison’s disease (74 %) (Gryczynska and Kosowicz 1991; Gut et al 2007, 2008). This may indicate that the presence of M-APA in patients with different autoimmune diseases and other pituitary problems is relatively common, but still their role is unclear.…”

“…Sera from five patients diagnosed with autoimmune polyglandular syndrome type II (APS II) with a previous record of the microsomal anti-pituitary autoantibodies confirmed by the same methodology (Gut et al 2008) were included as a positive control. All APS II patients were diagnosed with Addison’s disease and autoimmune thyroid disorder and two of them also suffer from vitiligo.…”

Diabetes Insipidus: A Pragmatic Approach to Management

“…Idiopathic central DI comprises almost one-fourth of cases [ 7 ]. AVP cell antibodies have been demonstrated in one-third of patients with idiopathic CDI [ 8 ].…”

The Hypothalamic–Pituitary Axis and Autoantibody Related Disorders

“…The search of pituitary auto-ags has been very extensive, carried out through different techniques. Indeed, through the immunoblotting on human pituitary, different bands have been revealed in sera from Graves’ disease patients, including those of 49 and 40-kDa [ 33 ]. APAs reactive to a 49-kDa pituitary cytosolic protein were found in 70% of biopsy-proven lymphocytic hypophysitis, 55% of suspected hypophysitis, but also in other diseases including Addison’s disease (42%), and pituitary tumors (20%), as well as in 9.8% of normal subjects [ 34 ].…”