Down's syndrome and autoimmunity.

A patient with Down's syndrome (DS) with multiple autoimmune phenomena is described. She suffered from hypothroidism, a celiac-like enteropathy and hemolytic anemia, and displayed cellular immunity directed against peripheral nerve antigen and basic myeloprotein and serum autoantibodies to many other tissue antigens. Her mother did not suffer from any overt autoimmune disease, but similar autoantibodies were found in her serum. It is suggested that DS resembles other autoimmune diseases, especially that which occurs in the NZB mice. The resemblance is based on the assumption that in both cases genetic and/or viral factors cause T-cell dysfunction which leads on the one hand to increased susceptibility to infections and leukemias, to autoimmune phenomena and to depressed cellular immunity, and on the other hand to increased B--cell reactivity.