Giant sigmoid diverticulum

This was a 75-year-old male who was admitted to the Gastroenterology Department for investigation of anaemia with Hb 9.10 g/dl. He reported an increase in the number of bowel movements (6–8 a day), sometimes with blood, and weight loss of 15 kg over the previous six months. He provided tests performed in a private centre, including gastroscopy, showing chronic gastritis and colonoscopy, showing diverticula and haemorrhoids. During the patient’s hospital stay, an abdominal CT was performed (Fig. 1) which identified diverticula in the sigmoid colon. MR colonography with contrast (Figs. 2 and 3) then showed a giant sigmoid diverticulum measuring about 10 cm. The patient was referred to general surgery and subsequently had elective surgery, leading to an improvement in his clinical condition.

Fig. 1.

Cross-sectional CT.

Fig. 2.

Coronal MRI.

Fig. 3.

Sagittal MRI.

Giant diverticula are defined as larger than 4 cm in size and are very rare. Most are the result of a valvular mechanism that prevents air from exiting the diverticulum.¹ Clinically, they tend to present with a palpable mass and abdominal discomfort. It is common for these diverticula to perforate because of the thinness of the wall, ischaemia and necrosis. In view of the risk of complications, surgical intervention is recommended, even in asymptomatic cases.²