Recurrent Fever and Abdominal Pain: Periodic Fever Syndrome, Inflammatory Bowel Disease or Patent Urachus; A Case Report

Introduction: The urachus is a duct that connects the allantois to the urinary bladder in the fetus. Partial or total obliteration failure of the urachus leads to various anomalies, which can be discovered in children and adults. Case Presentation: A12-year-old boy presented with recurrent fever and abdominal pain two years ago. In the physical examination, he had tenderness in the lumbosacral area and Achilles tendons. Enthesitis-related arthritis (ERA), inflammatory bowel disease (IBD), and familial Mediterranean fever (FMF) were considered differential diagnoses. The patient was treated with a naproxen anti-inflammatory dose. After 15 months, his mother reported a bad odor discharge from his umbilical area. Investigations revealed patent urachus, and he underwent an operation that confirmed the diagnosis and resolved the patient's complaints.