What are the next diagnostic steps after two CT scans?

From the Guidelines

After two CT scans, the next diagnostic steps should prioritize radiation-free alternatives, such as MRI or ultrasound, to minimize cumulative radiation exposure and potential cancer risk over time. The specific direction depends on what the CT scans revealed, the body area being investigated, and the suspected condition.

• Consulting with a specialist to determine if additional imaging or alternative diagnostic approaches are needed is crucial.
• Laboratory tests might also be ordered to complement imaging findings.
• A multidisciplinary team approach involving radiologists, specialists, and primary care physicians is often beneficial to interpret results comprehensively and develop the most appropriate diagnostic pathway forward 1.
• According to the WSES Guidelines, a step-up approach for diagnosis from clinical and laboratory examination to imaging examination should be used and tailored to the hospital's resources 1.
• The use of point-of-care ultrasound (POCUS) by non-radiologists has dramatically increased and could have a role in the diagnosis of acute diverticulitis and in those elderly patients who cannot undergo CT-scan 1.
• Recent studies suggest that alternative diagnostic approaches, such as US, MRI, or CT-scan without IV-contrast, can be used in patients who cannot undergo CT-scan with IV-contrast 1.

From the Research

Next Diagnostic Steps

After two CT scans, the next diagnostic steps may vary depending on the patient's condition and symptoms.

• If the patient has inflammatory bowel disease (IBD), colonoscopic surveillance is widely accepted as being effective in reducing the risk of IBD-associated colorectal cancer 2.
• The traditional recommendation has been quadrantic random biopsies throughout the entire colon; however, several guidelines now have endorsed chromoendoscopy with a target biopsy because of increasing diagnostic yields and reduced workloads for endoscopists and pathologists 2.
• New technologies such as narrow band imaging, confocal endomicroscopy, and autofluorescence imaging have not yet been confirmed as surveillance strategies in IBD 2.
• A study found that nearly 90% of colorectal cancer patients were diagnosed after development of symptoms and had more advanced disease than asymptomatic screening patients, highlighting the importance of screening colonoscopy 3.
• For patients with IBD, the risk of cancer is increased, and diagnosis and management of colorectal neoplasia in IBD are crucial 4.
• Post-colonoscopy colorectal cancers (PCCRCs) may account for up to 50% of all colorectal cancers diagnosed in patients with IBD, and the cumulative incidence proportions (CIPs) of PCCRC at 7-36 months after first-time and subsequent colonoscopies should be considered 5.
• In some cases, microscopic colitis (MC) may be a cause of chronic watery diarrhea, and the diagnosis requires histologic evaluation 6.

Diagnostic Considerations

• The approach to diagnosis should be guided by the severity of the patient's symptoms and medical history.
• A thorough evaluation of the patient's condition, including laboratory tests, endoscopy reports, and radiology reports, is necessary to determine the next diagnostic steps.
• The patient's risk factors, such as age, sex, and presence of other autoimmune diseases, should be taken into account when determining the diagnostic approach 6.