Left is right and right is left: a case report of gastric antral perforation in situs inversus totalis

Abstract

Situs inversus totalis (SIT) is a rare congenital anomaly in which thoracoabdominal organs are arranged in a complete mirror-image pattern. Although SIT does not increase the risk of gastrointestinal disease, it can obscure the diagnosis of acute abdominal emergencies because symptoms may appear on the opposite side. Gastric perforation in SIT is extremely uncommon, with very few cases reported worldwide. A 20-year-old male presented with two days of worsening abdominal pain and vomiting. Examination showed diffuse tenderness, guarding, rigidity, and liver dullness on the left side. A chest X-ray performed earlier revealed dextrocardia. At our centre, abdominal X-ray showed free air under the left hemidiaphragm. Computed tomography (CT) confirmed situs inversus totalis with complete visceral transposition and identified a right-sided gastric antral perforation. Emergency laparotomy revealed mirror-image anatomy of abdominal organs and great vessels. A 0.5×0.5 cm antral perforation near the lesser curvature on the right was repaired with primary closure and an omental patch. Recovery was uneventful, and the patient was discharged on postoperative day 10. SIT may delay diagnosis due to reversed symptom localisation. Early radiological evaluation, especially CT, is crucial for identifying organ transposition and guiding safe operative planning. Despite the inverted anatomy, standard surgical principles for small perforations remain effective. Gastric perforation in SIT is rare and easily missed. Prompt imaging, careful intraoperative orientation, and awareness of reversed anatomy enable safe surgical management and good outcomes.