autoimmune polyendocrine syndrome type 3 autoimmune polyendocrine syndrome type 3 autoimmune polyendocrine syndrome, type iii (aps iii) is a multi-system autoimmune disease characterized by lymphocytic infiltration of multiple endocrine and non-endocrine glands. in aps iii, autoimmune thyroiditis must be present, but the adrenal cortex is not involved. autoimmune polyendocrine syndrome, type iiiother namesautoimmune polyendocrinopathy type iii; aps iii or pas iiispecialtyendocrinology, rheumatologysymptomsany symptoms associated with its constituent diseasescomplicationsautoimmune thyroiditis (always), celiac disease, type i diabetes, autoimmune hypophysitis, systemic lupus erythematosus, sjögren's syndrome, vitiligo (may or may not be present)usual onsetany agedurationlifelongtypesaps 3a: autoimmune thyroiditis with immune mediated diabetes mellitus; aps 3b: autoimmune thyroiditis with pernicious anemia; aps 3c: autoimmune thyroiditis with vitiligo and/or alopecia and/or another organ specific diseasecausescombination of genetic and environmental factorsrisk factorsfamily history of aps iii or other autoimmune diseasesdiagnostic methodserum antibody assays; autoimmune thyroiditis required for diagnosisdifferential diagnosisautoimmune polyendocrine syndrome type ii, apeced, ipexpreventionn/atreatmentdepends on constituent diseasesprognosisnormal lifespanfrequency~ 2-3% of population aps iii is a member of a group of diseases, each known as an autoimmune polyendocrine syndrome. it is strongly related autoimmune polyendocrine syndrome type 2; however, type ii requires a diagnosis of addison's disease in addition to autoimmune thyroiditis. history autoimmune polyendocrine syndrome type iii was first rigorously defined in 1980 by physicians neufeld and blizzard in their classification of autoimmune polyendocrine syndromes. the distinction between types ii and iii is purely clinical, and any etiological difference was not yet outlined or discovered. the concept of polyendocrine failure originates from the work of german pathologist martin benno schmidt, who first described a patient with simultaneous adrenal insufficiency and hypothyroidism in 1926.