Left Upper-Quadrant Appendicitis in a Patient with Congenital Intestinal Malrotation and Polysplenia.

BACKGROUND Appendicitis is the most common cause of abdominal pain requiring emergent surgical intervention. Although typically presenting as right lower-quadrant pain, in rare cases it may present as left upper-quadrant pain secondary to abnormal position due to intestinal malrotation. Since atypical presentations may result in diagnostic and management delay, increasing morbidity and mortality, accurate and prompt diagnosis is important. Therefore, acute appendicitis should be considered in the differential diagnosis of left upper-quadrant abdominal pain. In this setting, medical imaging plays a key role in diagnosis. We report a case of a 13-year-old female with undiagnosed intestinal malrotation presenting with left-sided acute appendicitis. CASE REPORT A 13-year-old Hispanic female presented at the emergency room with anorexia and left upper-quadrant abdominal pain with involuntary guarding. The laboratory work-up was remarkable for elevated white blood cell count and elevated erythrocyte sedimentation rate. A nasogastric tube was placed and abdominal x-rays performed to rule-out bowel obstruction, showing distended bowel loops throughout all abdominal quadrants, with sigmoid and proximal rectal gas, raising concern for ileus rather than an obstructive pattern. Lack of symptomatic improvement prompted an IV contrast-enhanced abdominopelvic CT, revealing intestinal malrotation and with an inflamed left upper-quadrant appendix. Surgical management proceeded with a laparoscopic Ladd's procedure. CONCLUSIONS Acute appendicitis may present with atypical symptoms due to unusual appendix locations, such as in malrotation. Most cases are asymptomatic until development of acute complications, requiring imaging for diagnosis. Clinicians and radiologists should have a high index of suspicion and knowledge of its clinical presentations to achieve early diagnosis and intervention.