Inappropriate Use of Fecal Occult Blood Testing

Abstract

A 58-year-old man with bilateral knee osteoarthritis presented to the emergency department with 1 week of dizziness and intermittent dark stools. He denied dyspnea on exertion, angina, history of liver disease, or recent dietary or medication changes. Home medications included as-needed ibuprofen. On physical examination, he was afebrile, blood pressure was 100/65, and heart rate 98 beats per minute. Abdominal examination disclosed a soft, nontender, nondistended abdomen with normal bowel sounds. Digital rectal examination (DRE) revealed black, tarry, foul-smelling stool but no fresh or frank blood. Fecal occult blood testing (gFOBT) was performed reflexively after rectal examination and returned negative results. Laboratory testing results revealed hemoglobin 11.0 mg/dL (baseline, 13.6 mg/dL 3 months previously; to convert to g/dL, multiply by 10.0), platelets 278 000 mm 3 , blood urea nitrogen of 28 mg/dL (to convert to mmol/L, multiply by 0.357), serum creatinine of 0.98 mg/dL (to convert to μmol/L, multiply by 76.25), and normal coagulation parameters. He was admitted to the hospital but a gastroenterology consultation was initially deferred given the negative results from the FOBT. The admitting clinicians consulted gastroenterology 7 hours later when the patient again had a black tarry bowel movement. The patient was subsequently given intravenous pantoprazole, and upper endoscopic findings revealed three 1.5-cm duodenal ulcers, 1 of which had a visible vessel, which was treated with epinephrine injection and hemostatic clips. The ulcers were attributed to ibuprofen use. The patient was given oral pantoprazole on discharge to be taken for 2 months or as long as he continued to use ibuprofen. He had no recurrence of GI tract bleeding at 9 months' follow-up.

A Case for Abandoning Inpatient Fecal Occult Blood Testing

“…A negative gFOBT may lead to harm by delaying necessary investigations in this setting. One such case report in the literature detailed a patient with a negative gFOBT that had presented with melena and anemia [8]. The patient went on to have continued bleeding requiring transfusions and there was a delay in endoscopy because of a false negative gFOBT.…”

Medication Effects on Fecal Occult Blood Testing

“…Knowing this would have allowed for an appropriate interpretation of the result or, better yet, prevented it from being ordered at all. In Reply We thank Dr Wu for his comments on our article 1 and agree with him that multiple food items and medications can affect the interpretation of fecal occult blood testing (FOBT), thus making the test even more useless than we had alluded to in the article. It is very difficult to control for medications and diet in the hospital, a home diet history often is not obtained, and over-the-counter medications are frequently missed in a reconciliation.…”

“…The requirement to put the needs of patients above all else may very well be the psychosocial construct on which burnout begins in clinical practice. This meta-analysis 1 does not help us to determine the relative contribution of environment vs the innate personality characteristics of physicians who go on to develop burnout.…”

Medication Effects on Fecal Occult Blood Testing—Reply

“…Medications such as antiplatelet agents (eg, low-dose aspirin), nonsteroidal anti-inflammatory drugs, and oral anticoagulants can result in a false-positive FOBT owing to insignificant gastrointestinal losses. 2 The patient in this case 1 reported taking the nonsteroidal anti-inflammatory drug ibuprofen, which should have alerted the clinicians to recognize that a positive result would be uninterpretable as to whether it represented a significant or insignificant gastrointestinal bleed.…”

“…In Reply We thank Dr Wu for his comments on our article and agree with him that multiple food items and medications can affect the interpretation of fecal occult blood testing (FOBT), thus making the test even more useless than we had alluded to in the article. It is very difficult to control for medications and diet in the hospital, a home diet history often is not obtained, and over-the-counter medications are frequently missed in a reconciliation.…”