[Polyglandular autoimmune syndrome type II]

The polyglandular autoimmune syndrome type II, (Schmidts syndrome), is defined as coexistence of two of the diseases: Addison's disease, insulin dependent diabetes mellitus and autoimmune thyroid disease. The first endocrine deficiency state typically develops after the age of twenty and in most cases it is Addison's disease. The prevalence is approximately 5 per 100,000. The syndrome occurs within families in half of the cases. The immunological mechanism is not finally determined, but both the humoral and cellular systems seem to be involved and furthermore there is an association with the major histocompatibility complex. Whereas treatment of the components in polyglandular autoimmune syndrome is straightforward, diagnosis may be troublesome: Patients with Addison's disease may be biochemically hypothyroid the first months of corticosteroid treatment. Patients with myxedema show decreased urine excretion of 17-ketosteroids until thyroid substitution treatment is sufficient. A decreased insulin requirement or increased frequency of hypoglycaemic attacks may be the first sign of an adrenocortical hypofunction in diabetic patients. Patients with one autoimmune disease and their relatives are predisposed to (other) autoimmune diseases.