Autoimmune polyglandular syndrome (APS)

A genetic autoimmune disease with an extraordinary array of clinical features but characterized most often by at least 2 of the following 3 findings: hypoparathyroidism — underfunction of the parathyroid glands which control calcium, candidiasis (yeast infection), and adrenal insufficiency (underfunction of the adrenal gland). APS was the first systemic (bodywide) autoimmune disease found due to a defect in a single gene. By "autoimmune" is meant that the immune system (which normally wards off foreign invaders of the body) turns and attacks tissues such as skin, joints, liver, lungs, etc.) of the body. Examples of common systemic autoimmune diseases include rheumatoid arthritis, systemic lupus erythematosus, diabetes mellitus, Sjogren syndrome, scleroderma, Goodpasture syndrome, vitiligo, Addison disease, thyroiditis, and many others. In 1997 a novel gene was identified that mapped to chromosome region 21q22.3. The gene was named AIRE for autoimmune regulator. Changes in the AIRE gene are responsible for APS. APS is inherited as a recessive trait such that a child with the disease has received 2 changed (mutant) AIRE genes, one from each parent. Although APS is generally rare, it is more frequent in 3 genetically isolated populations: the Finnish, Iranian Jews, and Sardinians. The child with APS develops problems in numerous glands (polyglandular) including hypoparathyroidism, hypogonadism (with sex gland failure), adrenal insufficiency, type 1 (insulin-dependent) diabetes with insufficient insulin production by the pancreas gland, and latent hypothyroidism (underfunction of the thyroid gland). Other features of APS are total baldness (alopecia totalis), inflammation of the cornea and whites of the eye (keratoconjunctivitis), underdevelopment (hypoplasia) of the enamel of the teeth, childhood-onset moniliasis (yeast infection), juvenile-onset pernicious anemia, gastrointestinal problems (malabsorption, diarrhea), and chronic active hepatitis.