Evaluation of the total adenylate (ATP + ADP + AMP) test for cleaning verification in healthcare settings

INTRODUCTION: Evaluation of cleaning methods is the first step in the prevention of healthcare-associated infections. ATP hygiene monitoring tests are widely used for assessing the effectiveness of cleaning procedures. The test is easy to use and gives immediate results, however, ATP can be metabolized and degraded to ADP and AMP. Recently, a total adenylate [ATP + ADP + AMP(A3)] monitoring test has been developed. Our objective was to evaluate the usefulness of the A3 test for cleaning verification in healthcare settings. METHODS: The detection sensitivities of the ATP and the A3 tests were compared using blood, and debris derived from gloved-hand method and endoscopes immediately after endoscopic examination. The performance of the A3 test in monitoring cleanliness of high touch surfaces in the hospital and endoscopes at each cleaning step was also evaluated. RESULTS: For the hemolysate, the measurement values of the A3 test were stable, although ATP was promptly degraded. In debris from hands, the amount of A3 was 20 times higher than that of ATP. The detection sensitivities of the A3 test on residues derived from gastroscopes and colonoscopes were 3 and 8 times higher, respectively, than those from the ATP test. A field study indicated that a large number of microorganisms tend to show high A3 values on high touch surfaces in the hospital and on endoscopes. CONCLUSIONS: The A3 test showed higher detection sensitivities than the conventional ATP test for organic debris associated with healthcare settings.