Retrocaecal Appendicitis

retrocaecal appendicitis

This 36 year-old male presented with right loin-to-groin pain, and was thought to have renal colic despite absence of blood in the urine. A CT KUB was performed, and the sagittal image above shows the typical features of acute appendicitis. There are two appendicoliths in this retrocaecal appendix, a markedly distended lumen (appendix diameter 17mm, normal <6mm), and inflammatory stranding in the surrounding fat. The retrocaecal location may explain the atypical presentation, as the appendix is located more superiorly than usual, and is shielded from the examining doctor's probing fingers by the caecum. As the appendix lies adjacent to the psoas muscle, hyperextension of the right hip may elicit pain, a potentially helpful clinical sign. Interestingly,retrocaecal appendix can be familial.

This case highlights the utility of CT KUB – pathology outside the urinary tract can be demonstrated. It also highlights the downside – a routine plain film of the abdomen would probably have shown the appendicoliths, and led to the correct diagnosis at a much lower radiation cost.

Reference: Mann CV, Russell RC. Bailey & Love’s Short Practice of Surgery. 21st edition, Chapman & Hall Medical, 1992

Credit: Dr Laughlin Dawes