From the Guidelines
The test of choice for diagnosing diverticulitis is a CT scan of the abdomen and pelvis with intravenous and oral contrast, as it provides detailed visualization of the bowel wall, surrounding fat stranding, and potential complications such as abscesses or perforations 1. This imaging modality is preferred due to its high diagnostic accuracy, ability to identify complications, and guide treatment decisions.
Key Points
- CT scan is the most useful examination for patients with suspected colonic diverticulitis due to its reproducibility, superior diagnostic accuracy, and ability to identify complications 1.
- IV and oral contrast material may improve diagnosis of abscess by distinguishing from adjacent bowel, but unenhanced CT with oral contrast is less accurate than contrast-enhanced CT with oral contrast for the characterization of complications of diverticulitis 1.
- CT can predict unfavorable outcomes from acute diverticulitis, such as longer hospitalization, recurrence, and need for surgery, based on factors like abscess size, size of the inflamed diverticulum, and C-reactive protein levels 1.
- Ultrasound and MRI are alternative imaging modalities, but CT is generally preferred due to its high diagnostic accuracy, availability, and feasibility 1.
Clinical Considerations
- When a patient presents with symptoms suggestive of diverticulitis, a CT scan should be ordered promptly to confirm the diagnosis and assess disease severity.
- Laboratory tests, such as complete blood count, may support the diagnosis but are not specific.
- Colonoscopy is contraindicated during acute diverticulitis due to the risk of perforation, but may be recommended 6-8 weeks after resolution to rule out other pathologies like colorectal cancer.
From the Research
Diagnosis of Diverticulitis
- The test of choice for diagnosing diverticulitis is computed tomography (CT) scan, as it is both sensitive and specific in making a diagnosis of diverticulitis 2, 3, 4, 5, 6.
- CT scan is used to confirm the presence of diverticulitis, evaluate the disease severity and degree, and plan therapy in the presence of complications such as abscess or intestinal perforation 4.
- CT scan can also help differentiate diverticulitis from other diseases that may cause abdominal pain, such as neoplasm, inflammatory bowel disease, and colon ischemia 4.
Classification of Diverticulitis
- Diverticulitis can be classified as complicated or uncomplicated based on CT scan, severity of symptoms, and patient history 2.
- A radiological classification system has been created to guide the management of acute colonic diverticulitis, dividing it into two groups: complicated and uncomplicated 4.
- Complicated diverticulitis is further divided into four stages, depending on the presence of microperforation, abscess, and peritoneum involvement 4.
Role of CT in Management
- CT plays an important role in the management of diverticulitis, as it can help identify complications such as perforation, abscess formation, and fistulae 3.
- CT-guided drainage of diverticular abscesses can help reduce sepsis and permit a one-stage surgical operation 3, 5, 6.
- CT evidence of a diverticular abscess has a prognostic impact, as it correlates with a high risk of failure from nonoperative management regardless of the patient's age 5.