A Rare Case of Urachal Remnant with Calculus Just Below Umbilicus

Introduction: Urachal remnants, such as the vesicourachal diverticulum, or urachal cysts are rarely involved in calculus or calcification. There are currently no case reports of urachal remnants with calculus just below the umbilicus. Case Presentation: A healthy 28-year-old man presented with umbilical drainage. Abdominal computed tomography showed inflammation just below the umbilicus with calculus. The patient was diagnosed with ombilitis with a urachal remnant and underwent laparoscopic resection for the urachal remnant after the attenuation of ombilitis. Surgical findings showed that the omentum adhered to the abdominal wall along with the urachal duct. The urachal duct with calculus was resected at the top of the bladder. The main component of calculus was silicic acid. Pathological findings were compatible with a urachal remnant and there was no evidence of a malignant tumor. Discussion: The main component of calculus is derived from necrotic material caused by inflammation because silicic acid was detected, indicating a different etiology from that of urinary calculus. Conclusion: We encountered a rare case of a urachal remnant with calculus below the umbilicus.