Faecal haemoglobin and faecal calprotectin as indicators of bowel disease in patients presenting to primary care with...

Area of Science:

• Gastroenterology
• Diagnostic Accuracy
• Primary Care Medicine

Background:

• Assessing significant bowel disease in primary care is challenging.
• Faecal haemoglobin (FHb) and faecal calprotectin (FC) are potential diagnostic markers.
• Identifying patients with cancer, high-risk adenoma, or IBD requires accurate tools.

Purpose of the Study:

• To evaluate the diagnostic accuracy of FHb and FC in symptomatic patients.
• To determine the utility of these markers in identifying significant bowel disease.
• To assess the negative predictive values of FHb for colorectal cancer, adenoma, and IBD.

Main Methods:

• Prospective study of 1043 patients with bowel symptoms referred from primary care.
• Faecal samples analyzed for haemoglobin (FHb) and calprotectin (FC).
• Patients underwent colonic investigations; clinicians were blinded to faecal test results.

Main Results:

• FHb was detectable in 57.6% of samples; FC (≥50 µg/g) in 60.0%.
• Negative predictive values for FHb were 100% for colorectal cancer, 97.8% for high-risk adenoma, and 98.4% for IBD.
• Combining FHb and FC (≥200 µg/g) identified additional IBD and adenoma cases, but no further cancers.

Conclusions:

• Undetectable FHb serves as a reliable 'rule-out' test for significant bowel disease in primary care.
• FHb results can effectively guide the need for further investigation in symptomatic patients.
• These faecal markers aid in stratifying patients for endoscopic investigation.