Autoimmune polyendocrine syndrome
|Autoimmune polyendocrine syndrome|
|Classification and external resources|
In medicine, autoimmune polyendocrine syndromes, also called polyglandular autoimmune syndrome (PGAS), are a heterogeneous group of rare diseases characterized by autoimmune activity against more than one endocrine organ, although non-endocrine organs can be affected.
There are three "autoimmune polyendocrine syndromes", and a number of other diseases which have endocrine autoimmunity as one of their features.
- Autoimmune polyendocrine syndrome type 1 (APECED or Whitaker's syndrome)
- Autoimmune polyendocrine syndrome type 2
- The most serious but rarest form is the X-linked polyendocrinopathy, immunodeficiency and diarrhea-syndrome, also called XLAAD (X-linked autoimmunity and allergic dysregulation) or IPEX (immune dysfunction, polyendocrinopathy, and enteropathy, X-linked). This is due to mutation of the FOXP3 gene on the X chromosome. Most patients develop diabetes and diarrhea as neonates and many die due to autoimmune activity against many organs. Boys are affected, while girls are carriers and might suffer mild disease.
Other diseases featuring polycrine autoimmunity:
- Chromosomal abnormalities (Down syndrome) increase the risk of endocrine autoimmunity
- POEMS syndrome - the E is for endocrinopathy; the cause is a paraprotein excreted by a plasmacytoma or multiple myeloma; other features are polyneuropathy, organomegaly (hepatomegaly and splenomegaly), M-protein (paraprotein) and skin changes.
- Several very rare diseases including Lupus and Addison's Disease.
In principle, the component diseases are managed as usual. The challenge is to detect the possibility of any of the above syndromes, and to anticipate other manifestations. For example, in a patient with known Type 2 autoimmune polyendocrine syndrome but no features of Addison's disease, regular screening for antibodies against 21-hydroxylase (a feature of Addison's) may prompt early intervention and hydrocortisone replacement to prevent characteristic crises.
- "Polyglandular Autoimmune Syndromes: Immunogenetics and Long-Term Follow-Up". Retrieved 1 July 2013.
- Eisenbarth GS, Gottlieb PA (2004). "Autoimmune polyendocrine syndromes". N. Engl. J. Med. 350 (20): 2068–79. doi:10.1056/NEJMra030158. PMID 15141045.
- Yong PL, Russo P, Sullivan KE (May 2008). "Use of Sirolimus in IPEX and IPEX-Like Children". J. Clin. Immunol. 28 (5): 581–7. doi:10.1007/s10875-008-9196-1. PMID 18481161.