Sigmoid Volvulus in an Elderly Man

Elderly man with sudden, severe abdominal pain

A 72-year-old man is brought to the emergency department by his wife. Hecomplains of nausea, vomiting, and severe abdominal pain that makes it difficultfor him to walk. The pain began the previous afternoon and has worsened steadily.The patient denies trauma and recent foreign travel. His history includes an appendectomyperformed many years earlier but is otherwise noncontributory.

Temperature is 37.7^oC (100^oF); heart rate, 127 beats per minute; respirationrate, 26 breaths per minute; and blood pressure, 80/50 mm Hg. Exceptfor tachycardia and tachypnea, heart and lungs are normal. The abdomen ismoderately distended but soft; there is severe tenderness with guarding butno rebound tenderness.

You order an abdominal radiograph. What abnormality does this filmreveal, and what further workup is required to arrive at a diagnosis?

Figure B

Figure C

Elderly man with sudden, severe abdominal pain: Thesupine radiograph reveals a very large dilated loop of bowelin the upper abdomen that has a "coffee bean" shape(A, white arrow). On close inspection, this loop has haustralmarkings, which identify it as colon. In addition, gascan be seen in both the ascending colon and descendingcolon (A, yellow arrows).

You order a CT scan with contrast to investigate theabnormality. An axial image at the level of the kidneysconfirms the presence of dilated bowel (B, arrow). Thereis no evidence of pneumatosis or bowel-wall thickening.An image at the level of the iliac crests shows a prominentgas-fluid level in the ascending colon, which would correlatewith an obstruction (C, arrow). This image also confirmsthat there are no dilated loops of small bowel. Athird CT image, at the level of the middle pelvis, revealscontrast in the bladder and rectum (D). Careful inspectionshows that the rectosigmoid junction has a "beaked"appearance (arrow).

You order a limited barium enema, which confirmsthe beaked appearance of the rectosigmoid junction (E,arrow). This finding is diagnostic of sigmoid volvulus.

In patients who have sigmoid volvulus, the sigmoidcolon twists on its mesenteric axis; the degree of torsioncan vary. A typical radiographic feature on conventionalsupine images of the abdomen is the coffee bean sign-a dilated loop of colon that extends toward the diaphragm.This loop has a distinct midline crease that represents themesenteric root of the volvulus.

Figure D

Figure C

The most common sites for colonic volvulus are thesigmoid colon, which accounts for approximately 70%of cases, and the cecum, which accounts for the remaining30%. Because the sigmoid colon becomes stretchedand elongated with age, older persons are especially susceptibleto sigmoid volvulus.

In cecal volvulus, an elongated mesentery can typicallybe identified on a radiograph. Cecal volvulus can be associatedwith malrotation and is generally seen in youngerpatients aged 20 to 40 years.

Outcome of this case. Sigmoidoscopy with rectaltube insertion was performed to decompress the volvulus.Following decompression, the patient's symptomsresolved. The patient was subsequently dischargedand lost to follow-up.