Rectal bone bezoar: an unusual finding

Description

A 60-year-old woman with an anxiety disorder presented with diarrhoea, rectorrhagia, tenesmus and proctalgia, progressively worsening for the past 2 months, in association with significant weight loss (15% body weight). Physical examination included a painful digital rectal examination, which identified a hard and spiculated mass immediately above the anal canal.

Abdominopelvic X-ray showed a calcic-density 7 cm hypotransparent mass in the rectum. Evaluation by CT revealed a large, heterogeneous 72×44×43 mm bone density mass located in the rectal ampulla and associated with rectal wall thickening, in addition to several other small foci of calcium density, identified throughout the entire colon (figure 1).

Figure 1.

Abdominopelvic X-ray showing a calcic hypotransparent mass in the rectal region (left). CT sagittal images revealing intraluminal bone-density masses in the colon and rectum (right).

Rectosigmoidoscopy confirmed the presence of the mass consisting of multiple bird bones, mostly vertebrae, impacting on the rectum (figure 2). Using the anoscope and a Magill clamp, it was possible to remove, bone by bone, the entire rectal bezoar and multiple traumatic ulcerations of the rectal mucosa were identified (figure 2). Using the colonoscope, the entire colon was evaluated and the remaining bone fragments were removed. The patient has remained asymptomatic and without complications over a period of 18 months of follow-up so far.

Figure 2.

Endoscopic images of the rectum with a large mass consisting of multiple bone fragments (left) and the traumatic ulcerations of the rectal mucosa after successful bone removal (right).

We describe a case of successful resolution of a bone bezoar impacted in the rectum, using anoscopy and endoscopy. 'To the best of our knowledge, there are few cases of bone bezoars described in the literature, referring mainly to the small bowel, with only two cases of obstruction in the rectum.^1–3

Learning points.

• Rectal bezoars are rare, but can mimic the clinical presentation of a colorectal cancer.

• After initial identification of the rectal mass by digital rectal examination, radiological evaluation allows a more precise definition of its characteristics and location.

• Endoscopic techniques, due to their low aggressiveness, should be the first choice to remove a bezoar.