title: A comparative study of eight fecal occult blood tests and HemoQuant in patients in whom colonoscopy is indicated.
abstract: OBJECTIVE
  Some studies suggest that immunochemical fecal occult blood tests (FOBTs) and HemoQuant are more efficient at detecting fecal occult blood than the commonly employed Hemoccult II (guaiac) test. We undertook this study to determine whether an immunochemical test either alone or in combination with a guaiac test gives efficiency superior to the Hemoccult II test in predicting significant gastrointestinal tract disease.
  
  
  METHODS
  Criterion standard, prospective, blinded.
  
  
  METHODS
  Referral population of ambulatory patients at an institutional and a private hospital.
  
  
  METHODS
  Eight-one patients referred to a gastroenterologist and in whom colonoscopy was indicated.
  
  
  METHODS
  While on a restricted diet, patients made preparations for FOBTs from three consecutive bowel movements. Patients then underwent colonoscopy. Polyps larger than 1 cm in size, carcinoma of the colon, peptic ulcers, gastric erosions, and angiodysplasia were considered to be likely causes of occult gastrointestinal tract bleeding.
  
  
  METHODS
  Using colonoscopy results as the reference standard, sensitivity, specificity, and positive and negative predictive values for each of eight tests or pair of tests were compared with those of Hemoccult II.
  
  
  RESULTS
  Of 81 patients, 10 had significant lower gastrointestinal tract lesions and six had significant upper gastrointestinal tract lesions. Hemoccult SENSA, Heme-Select, and FECA-EIA were shown to be more sensitive than Hemoccult II but slightly less specific. Paired tests showed less efficiency than Hemoccult II alone.
  
  
  CONCLUSIONS
  We did not find an ideal test or pair of tests; however, Hemoccult SENSA exhibited higher sensitivity than Hemoccult II and many other tests. The sensitivity, specificity, and positive predictive values of many of the FOBTs were believed to be low. We recommend that physicians consider FOBTs only as adjuncts to history and physical examination findings in deciding how to proceed in diagnosing gastrointestinal tract disease.
authors: Department of Medicine, Wright State University School of Medicine, Dayton, Ohio.
authors: N
authors: N
authors: Gopalswamy
authors: H P
authors: HP
authors: Stelling
authors: R J
authors: RJ
authors: Markert
authors: H N
authors: HN
authors: Maimon
authors: S D
authors: SD
authors: Wahlen
authors: R I
authors: RI
authors: Haddy
mesh_terms: D003113:Colonoscopy; D003937:Diagnosis, Differential; D005767:Gastrointestinal Diseases / Q000175:diagnosis*; D006801:Humans; D009780:Occult Blood; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016037:Single-Blind Method