Foreign Body-induced Appendicitis in Situs Inversus Totalis: Diagnostic and Management Challenges in the Emergency Department: a Rare Case Report.

Introduction: Situs inversus totalis (SIT) is a rare congenital condition in which the major visceral organs are mirrored from their normal positions. Appendicitis in patients with SIT can be diagnostically challenging due to the atypical location of abdominal pain, typically presenting on the left side. Foreign body impacted appendicitis is a rare occurrence.

Case Presentation: We present a case of a 10-year-old boy presented to the emergency room with complaints of abdominal pain in the left lower abdomen. Acute appendicitis with an impacted foreign body in the lumen of the appendix was found in ultrasonography (USG). Chest X-ray showed dextrocardia and fundic gas under the right hemidiaphragm and the liver shadow on the left illustrating SIT. The patient underwent an urgent midline laparotomy, revealing a left iliac fossa appendix consistent with situs inversus. The inflamed appendix contained a palpable foreign body. The appendix was excised, revealing a sewing machine pin approximately 5 cm in length lodged in the appendiceal lumen.

Discussion: Situs inversus totalis is a rare condition in which the orientation of visceral organs mirrors the normal anatomy. Abdominal pain is one of the most frequent chief complaints among patients in the Emergency department, with appendicitis being the most common surgical condition diagnosed. Left-sided lower abdominal pain can be the presentation of appendicitis in situs inversus totalis. Usual presentation is right-sided pain so doctors do not consider left-sided lower abdominal pain as differential diagnosis of acute appendicitis making atypical presentation difficult to diagnose. Failure to consider this anatomical variation could delay diagnosis, leading to misinterpretation of symptoms and unnecessary or inappropriate investigations.

Conclusion: In cases of left lower quadrant pain with dextrocardia and right-sided gastric gas bubble on chest X-ray should be thought of acute appendicitis. USG or computed tomography abdomen must be done to diagnose appendicitis with an impacted foreign body in SIT.