Early-onset Chronic Keratitis as the First Presenting Component of Autoimmune Polyendocrine Syndrome Type 1: A Case Report and Review of the Literature

Autoimmune polyendocrine syndrome type 1 (APS-1), also referred to as autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy, is a rare monogenic autosomal recessive autoimmune disease. It is caused by mutations in the autoimmune regulator (AIRE) gene. APS-1 is diagnosed clinically by the presence of two of the three major components: chronic mucocutaneous candidiasis, hypoparathyroidism (HPT), and primary adrenocortical insufficiency. A 3.3-year-old girl presented with a carpopedal spasm to the pediatric emergency clinic. She had a history of recurrent keratitis, and chronic candidiasis, manifesting as urinary tract infections and oral thrush. HPT was diagnosed based on low serum concentrations of calcium and parathyroid hormone and elevated serum concentrations of phosphate, and treatment with calcium and calcitriol supplementation was started. Genetic testing identified a homozygous nonsense mutation, c.769C>T (p.R257X), in exon 6 of AIRE which has been reported previously. At the age of 5.6 years, she presented with adrenal crisis, and treatment with hydrocortisone and fludrocortisone was started. This case demonstrates that unexplained chronic keratitis in children may be the first and most severe component of this syndrome. The classic triad of APS-1 may also appear in the first decade of life.