Precocious presentation of autoimmune polyglandular syndrome type 2 associated with an AIRE mutation

• Published in: Hormones (Athens, Greece) Vol. 14; no. 2; pp. 312 - 316
• Main Authors: Resende, Eduarda, Gómez, Gemma Novoa, Nascimento, Marta, Loidi, Lourdes, Fiaño, Rebeca Saborido, Rodríguez, Paloma Cabanas, Castro-Feijoo, Lidia, Conde, Jesús Barreiro
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.04.2015
• Subjects: AIRE Protein; Case Report; Child; Diabetes Mellitus, Type 1 - complications; Diabetes Mellitus, Type 1 - genetics; Endocrinology; Female; Genetic Predisposition to Disease; Humans; Medicine; Medicine & Public Health; Metabolic Diseases; Mutation; Polyendocrinopathies, Autoimmune - complications; Polyendocrinopathies, Autoimmune - diagnosis; Polyendocrinopathies, Autoimmune - genetics; Transcription Factors - genetics; Autoimmune Regulator gene; Type 2 APS; Autoimmune polyglandular syndrome; Mutation; AIRE gene; Child; Schmidt’s syndrome
• ISSN: 1109-3099; 2520-8721
• DOI: 10.14310/horm.2002.1513

Autoimmune polyglandular syndrome type 2 (type 2 APS), or Schmidt’s syndrome, is defined by the presence of Addison’s disease in combination with type 1 diabetes and/or autoimmune thyroid disease. The estimated prevalence of this syndrome is 1.4–4.5 per 100,000 inhabitants and it is more frequent in middle-aged females, whilst it is quite rare in children. Type 2 APS, which shows a pattern of autosomal dominant inheritance with low penetrance, has been associated with HLA specific DR3/DQ2 and DR4/DQ8 haplotypes. However, it has been hypothesized that genetic variability in the AIRE gene, which causing type 1 APS, may play a role in more common organ-specific autoimmune conditions like type 1 diabetes, Hashimoto’s disease and type 2 APS, among others. Here we present the case of an 8-year-old girl, with a past medical history of type 1 diabetes diagnosed at the age of 3. She was taken to the Emergency Department because she complained of abdominal pain, nausea and vomiting, and her blood analysis revealed a severe hyponatremia. She also had seizures as a consequence of the hyponatremia and frequent hypoglycemia. She was ultimately found to be suffering from autoimmune primary adrenal insufficiency. The combination of both mentioned conditions, type 1 diabetes and Addison’s disease, in the absence of chronic mucocutaneous candidiasis, made a diagnosis of type 2 APS plausible in this girl. The genetic study showed two heterozygous variants: NM_000383.2:C.1411C>T (p. Arg471Cys) in exon 12 and IVS9+6G>A in intron 9 of the AIRE gene. The description of an uncommon case of type 2 APS with precocious presentation associated with an AIRE mutation in a very young girl could help to clarify the role of AIRE in the development of autoimmune diseases.