Faecal occult blood testing in patients with colonic symptoms.

Faecal occult blood testing with Hemoccult is becoming popular as a means of detecting colorectal carcinoma or adenoma. In determining its diagnostic place, such testing must be evaluated in patients with colonic symptoms as well as in asymptomatic populations. False negative test results may be determined either by full colonic investigation of screened patients or by their long-term follow-up. One hundred patients with colonic symptoms were screened with Hemoccult testing, sigmoidoscopy, and a barium-enema X-ray examination. Eight of 10 patients with proven colorectal carcinoma showed a positive Hemoccult test result, as did two of seven patients with proven colorectal adenomatous polyps. A negative Hemoccult test result in patients with colorectal symptoms does not exclude either colorectal carcinoma or adenoma; however, a positive result does usually indicate the presence of organic gastrointestinal disease.