[Selection of Laboratory Procedures to Detect Toxigenic by the 2-Step Method].

Abstract

The 2-step method is an algorithm to detect toxigenic <i>Clostridium difficile</i>. We herein compared the sensitivities and specificities of an enzyme immunoassay (toxin A/B-EIA), toxigenic culture (TC-EIA), Loop-Mediated Isothermal Amplification assay (LAMP), and Xpert <i>C. difficile</i> (Xpert) with the detection of the toxin B gene by a polymerase chain reaction (PCR). The results obtained showed that the sensitivities and specificities of toxin A/B-EIA, Xpert, TC-EIA, and LAMP were 30 and 100%, 87.2 and 100%, 97.5 and 89.7%, and 95 and 100%, respectively. We also evaluated the turnaround time (TAT) and cost of toxigenic <i>C. difficile</i> detection. Our hospital TAT for toxin A/B-EIA and TC-EIA are 37 min and 5 days, respectively. We estimated the TAT of Xpert, LAMP, and PCR to be 105 min, 5 days, and 6 days, respectively. On the other hand, the cost to detect toxigenic <i>C. difficile</i> increased in the order of TC-EIA, LAMP, Xpert, and PCR. We have never experienced outbreak of <i>Clostridium difficile</i> infection (CDI) in our hospital, and there is less the number of CDI than other place. So we selected TC-EIA that is good sensitivity and low cost per specimen. Hereafter it'll be necessary to solve a problem it takes time, because we have to respond to outbreak of CDI quickly if it happens.