From the Guidelines
The coffee bean sign is a critical radiological finding that indicates sigmoid volvulus, a potentially life-threatening condition requiring prompt intervention, usually through sigmoidoscopic decompression or surgery if decompression fails or if there are signs of bowel ischemia. The sign appears as a dilated loop of bowel resembling a coffee bean or kidney bean shape, typically positioned in the upper or middle abdomen, as described in the WSES consensus guidelines on sigmoid volvulus management 1. This distinctive appearance occurs because the twisted loop creates two adjacent lumens separated by the walls of the sigmoid colon, forming the central cleft of the "bean."
Clinical Presentation and Diagnosis
The coffee bean sign is important for emergency diagnosis as sigmoid volvulus requires prompt intervention. The condition most commonly affects elderly patients, particularly those with chronic constipation or institutionalized individuals with neuropsychiatric conditions, as noted in the study by Raveenthiran et al. 1. The twisting occurs due to a redundant sigmoid colon with a narrow mesenteric attachment, which predisposes it to rotation around its mesenteric axis, leading to bowel obstruction and potential ischemia if not treated quickly.
Key Points to Consider
- The coffee bean sign is a diagnostic feature of sigmoid volvulus, which can be identified on plain abdominal radiographs or CT scans 1.
- Prompt intervention is necessary to prevent complications such as bowel ischemia and perforation.
- Sigmoidoscopic decompression is the first line of treatment for uncomplicated sigmoid volvulus, while surgery is recommended for complicated cases or if decompression fails 1.
- The optimal treatment approach depends on the patient's initial presentation, with urgent upfront surgery warranted for patients with septic shock, bowel ischemia, or perforation 1.
Recommendations for Management
The management of sigmoid volvulus should prioritize prompt intervention, with a focus on preventing complications and improving patient outcomes. This includes:
- Initial evaluation with a focused history, physical examination, and blood tests to identify signs of bowel ischemia or perforation 1.
- Diagnostic imaging with plain abdominal radiographs or CT scans to confirm the diagnosis of sigmoid volvulus 1.
- Sigmoidoscopic decompression as the first line of treatment for uncomplicated cases, with surgery reserved for complicated cases or if decompression fails 1.
From the Research
Definition and Diagnosis of Coffee Bean Sign
- The coffee bean sign is a radiographic sign that is pathognomonic of sigmoid volvulus 2.
- It is characterized by a plain abdominal X-ray demonstrating a coffee bean-shaped appearance, indicating a sigmoid volvulus 3, 4.
- The sign is often associated with other radiographic signs, such as the steel pan sign and the whirl sign, which can confirm the diagnosis of sigmoid volvulus 4.
Clinical Presentation and Treatment
- Sigmoid volvulus is an abdominal emergency that requires urgent treatment, particularly in elderly patients 3.
- Patients may present with abdominal distension, diarrhea, and other symptoms, but may not always exhibit abdominal pain or muscular defense 3.
- Treatment options include emergency colonoscopy, which can be an effective conservative primary treatment for acute sigmoid volvulus 3.
- Colonoscopic decompression and detorsion can improve symptoms and prevent relapse 4.
Radiographic Signs
- The coffee bean sign is a key radiographic sign in the diagnosis of sigmoid volvulus 3, 4, 2.
- Other signs, such as the steel pan sign and the whirl sign, can also be present and confirm the diagnosis 4.
- A plain abdominal X-ray and CT scan can be used to demonstrate these signs and confirm the diagnosis of sigmoid volvulus 3, 4.
Note: The study 5 is not relevant to the topic of coffee bean sign and sigmoid volvulus.