The presence of immunoglobulin D in endocrine disorders and diseases of immunoregulation, including the acquired immunodeficiency syndrome.

Immunoglobulin D (IgD) was determined by double diffusion in the serum from 26 patients with endocrine disorders and diseases of immune imbalance along with controls. IgD was detected in the serum of nine patients that included two with primary parathyroidism, one with insulin-resistant diabetes, four with immunodeficiencies, and two with Hodgkin's disease. IgD was absent in the serum of seven patients with the same diagnoses after treatment. IgD was present in the serum of the majority of acquired immune deficiency syndrome patients (in eight of ten cases). The presence of IgD in the serum of these patients suggests that it plays a role in receptor-mediated events.