Giant sigmoid diverticulum: a rare cause of common gastrointestinal symptoms

A 75-year-old woman was admitted to the emergency department (ED) with a history of vague abdominal pain associated with meteorism, nausea and occasional vomiting. Over the 6–7 months prior to admission, the symptoms had been characterized by periods of exacerbation, alternating with spontaneous remission. During this period, the patient had been periodically treated with a symptomatic pharmacological approach, with consequent alleviation of the symptoms. Before hospitalization, no laboratory tests, radiological screening or colonoscopic surveillance had been carried out. When the patient came to our unit, she presented the abdominal symptoms described above with stable vital signs and was afebrile. On physical examination, the abdomen was mildly tender to palpation in the middle and lower quadrants with no signs of peritonitis. No abdominal mass was felt during abdominal palpation. A digital rectal examination gave no clues, while laboratory tests yielded a positive result for occult blood in the faeces. Laboratory tests also revealed a white blood cell count of 18.3 9 10/lL (normal value: 4.5–10.8 9 10/lL) with a mild increase in the neutrophil cells and an iron deficiency anaemia. A plain abdominal X-ray study demonstrated a large, rounded, radiolucent formation (12 cm 9 22 cm) in the middle and lower abdomen, with no signs of obstruction (Fig. 1a, b). The subsequent unenhanced CT scan presented an image of an air-filled structure with thin regular walls and a narrow neck, opening into the sigmoid colon. The inner part of this structure contained a small quantity of fluid. The presence of this formation was confirmed by 2D MPRs in the sagittal and coronal plane (Fig. 2a, b). The mass was diagnosed as a giant sigmoid diverticulum (GSD). Multiple other diverticula were present in the descending colon. The patient underwent sigmoid resection with primary anastomosis, without further complications.