Yield of dual endoscopy for positive fecal occult blood test

Dual endoscopy is frequently performed on the same day in patients whose stools are found to be positive on fecal occult blood testing (FOBT). This is often done to localize the potential sources of GI bleed. The diagnostic yield of same day dual upper endoscopy (EGD) and lower endoscopy (colonoscopy) for the detection of positive FOBT is uncertain. In the era of cost-efficient medical practice, we investigated whether a more evidence-based and structured approach could be used to guide physicians to the workup of patients who present with positive FOBT.

We performed a retrospective analysis of 309 patients, and 260 patients from this population met our inclusion criteria. Inclusion criteria included FOBT without acute GI hemorrhage, hematochezia, or melena. Patients were required to have had EGD and colonoscopy within the same day (<24 h).

Of 260 patients, a total of 135 (52%) patients had positive findings on colonoscopy and a total of 42 (16.1%) patients had positive findings on EGD. Sixteen (6.1%) had positive EGD and negative colonoscopy; 109 (42%) had positive colonoscopy and negative EGD; and 26 (10%) had positive findings on both EGD and colonoscopy.

Colonoscopy should be chosen as the initial procedure of choice in the evaluation of patients who present with positive FOBT. Same day dual endoscopy does not seem to be cost-effective.