Iatrogenic rectal perforation. ct findings.

A 74-year-old women with abdominal pain and constipation. On exploration the abdomen was depresible , the blood test was normal and the abdominal X-ray didn´t show any obstruction findings. During her stay in emergency service, analgesia and a cleasing rectal enema was performed without any improvement. Afterwards the patient started with overall disconfort and rectal bleeding, so an urgent CT was done. The CT showed presacral and perirrectal extraluminal free fluid and extraluminal air, especially next to the anterior wall of low rectum close to the anorrectal angle, and also free fluid in retroperitoneal space.

The patient was operated, and the rectal perforation was confirmed. Most of iatrogenic colorrectal perforations are due to endoscopic procedures as biopsies or polypectomy , while those who are associated with an increased of hydrostatic pressure (as in our patient, due to a cleasing enema), are very infrequent, this is due to the anal sphincter acts as a protector barrier against the increase of pressure (1). The most frequent cause of perforation in patients who underwent enema have been reported to be the device tip, other causes are related to localized weakness of the rectal wall, obstruction, or the position of the patient when the enema was performed (2). CT plays a essential role in diagnosis and location of colorrectal perforations, showing extraluminal air, extraluminal free fluid, interruption or abnormalities of the colonic wall and inflamatory changes close to the wall. Rectal perforations, that occur below the peritoneal reflexion, lead to retroperitoneal air dissection and have a better clinical course compared with intraperitoneal perforations (3).

Cleasing enemas can be very effective in the treatment of constipation but may cause serious adverse events, such as perforation or metabolic derangement. In case of perforation a rapid diagnosis is essential to get an appropriate management and surgical planning, being the CT the diagnosis method of choice when we suspect a perforation.

- Wha Choi P. Colorectal perforation by self-induced hydostatic pressure: A report of two cases. The Journal of Emergency Medicine, 2013, 44 (2): 344–348. - Niv G, Grinberg T, Dickman R, Wasserberg N, Niv Y. Perforation and mortality after cleansing