Symptoms are that of a large bowel obstruction: constipation, abdominal bloating, nausea and/or vomiting. Onset may be acute or chronic.
There is a wide range of causes, some are region-specific 5:
- chronic constipation and/or laxative abuse
- fibre-rich diet (especially in Africa)
- Chagas disease (especially in South America)
- chronic neurological conditions (e.g. Parkinson disease, multiple sclerosis, pseudobulbar palsy)
- medications from chronic psychiatric conditions (e.g. chronic schizophrenia)
Abdominal radiographs will show a large, dilated loop of colon, often with a few air-fluid levels. Specific signs include:
- coffee bean sign 5
- Frimann Dahl's sign - three dense lines converge towards site of obstruction
- absent rectal gas 5
Although now uncommonly performed, a water soluble contrast enema exquisitely demonstrates this condition, with the appearances described as the beak sign (or bird beak sign).
- large gas-filled loop without haustral markings, forming a closed-loop obstruction 6, 7
- whirl sign: twisting of the mesentery and mesenteric vessels
- beak sign: if rectal contrast has been administered 6
Treatment and prognosis
Rectal tube insertion is successful in treating 90% of cases 5. Mortality rate is 20-25% 7. The most serious complication is bowel ischaemia.
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- 7. Brant WE, Helms CA. Fundamentals of Diagnostic Radiology. Lippincott Williams & Wilkins. (2007) ISBN:0781761352. Read it at Google Books - Find it at Amazon