Retroperitoneal appendicitis within a posterior abdominal wall incisional hernia secondary to a right nephrectomy: a first incidence case report

Appendiceal herniation is rare and typically described in inguinal or femoral hernias. Retroperitoneal appendicitis within a nephrectomy incisional hernia has not previously been reported. A 65-year-old woman with a history of flank approach right nephrectomy presented with migratory flank-to-umbilical pain and raised inflammatory markers. Computed tomography demonstrated acute appendicitis herniating through a posterolateral abdominal wall defect at the prior nephrectomy site. She underwent open appendicectomy via the original flank incision, followed by single-stage hernia repair using biological mesh. Postoperative recovery was uncomplicated apart from a small conservatively managed seroma, and histopathology confirmed acute appendicitis. This case highlights a previously undescribed presentation of appendicitis and underscores the importance of individualized operative planning when considering concurrent hernioplasty in a potentially contaminated field.