Acute appendicitis in a malpositioned appendix leading to retroperitoneal abscess and sepsis: a forensic autopsy case.

We report an autopsy case of a 74-year-old man with lower back pain who was referred to an orthopedic surgeon. Three days after he was prescribed acetaminophen for lumbar disc herniation, he was found dead in his bed. The autopsy revealed a perforated appendicitis attached to the retroperitoneum in the upper right abdomen, massive hemorrhages in the cecum, a retroperitoneal abscess, and skin discoloration from the abdomen to the back. The patient had died from sepsis caused by a retroperitoneal abscess and soft tissue infection secondary to perforated appendicitis adhering to the retroperitoneum. The C-reactive protein level was 43.5 mg/dL. Typically, perforated appendicitis causes peritonitis and sepsis. However, in our patient, intraperitoneal inflammation was limited to the region around the appendix, with no involvement of the surrounding intraperitoneal organs and no signs of peritonitis. Therefore, we speculated that appendiceal displacement was associated with retroperitoneal abscess. To our knowledge, this case study presents a rare case of retroperitoneal abscess caused by appendicitis.