Abstract
Autoimmune enteropathy is a rare cause of chronic intractable diarrhea and is present in <1 in 100,000 infants. We report the case of a 9-month-old boy who presented with intractable diarrhea and vomiting. Genetic panel testing revealed a STAT3 heterozygous mutation in exon 6, suggesting infantile-onset multisystem autoimmune disease-1. The patient was initially treated with steroids and sulfasalazine. However, on tapering steroids, he had another episode of diarrhea and was subsequently put on baricitinib to which he responded.