The poppy-seed test is a cheap and accurate diagnostic tool for colovesical fistula

Kwon EO et al. (2008) The poppy seed test for colovesical fistula: big bang, little bucks! J Urol 179: 1425–1427

Patients with suspected colovesical fistula often undergo a series of expensive diagnostic tests and procedures, each of which have limitations. No consensus exists on the best approach to diagnosis. The poppy-seed test—which involves ingestion of poppy seeds and visual inspection of urine for the presence of the seeds during 48 h—is a simple diagnostic tool for colovesical fistula. Kwon and colleagues compared the accuracy and cost-effectiveness of this diagnostic tool with that of ⁵¹Cr nuclear study and CT.

The study included 20 patients (median age 74 years, 14 male) who were confirmed to have a colovesical fistula at surgery. Preoperatively, the patients were evaluated by CT of the abdomen and pelvis with oral and intravenous contrast medium, a ⁵¹Cr nuclear study and the poppy-seed test; results and costs of each test were recorded.

The most expensive technique was CT, at US$652.92 per study. This modality also had the lowest detection rate (70%). The ⁵¹Cr nuclear study cost $490.83 per study and had a detection rate of 80%. The poppy-seed test was both the least expensive ($5.37 per study) and had the highest detection rate (100%).

In this small study, the poppy-seed test proved accurate, inexpensive and convenient. The authors suggest that it could be used as a cost-effective preliminary test for colovesical fistula, to identify patients who require further evaluation (e.g. detailed localization of the fistula by CT).