Does a rapid diagnosis of Clostridium difficile infection impact on quality of patient management?

A rapid and accurate diagnosis of Clostridium difficile infection (CDI) is essential for patient management and implementation of infection control measures. During a prospective time-series study, we compared the impact of three different diagnostic strategies on patient care. Each strategy was tested during a 3-month period: P1 (diagnosis based on the stool cytotoxicity assay and the toxigenic culture), P2 (diagnosis based on PCR) and P3 (two-step algorithm based on glutamate dehydrogenase detection followed by nucleic acid amplification test). The following criteria were used to assess the quality of patient management: (i) time for result reporting, (ii) frequency of repeat testing within 7days, (iii) time elapsed between stool collection and beginning of treatment for patients with CDI, and (iv) frequency of empirical treatment for patients without CDI. Of 1122 stool samples (P1 n=359, P2 n=374, P3 n=389), 36 (10.0%), 47 (12.3%) and 48 (12.3%) were positive for C.difficile during P1, P2 and P3, respectively. The time for reporting of a positive or a negative result was significantly shorter and the frequency of redundant stool samples within 7days was lower during P2 and P3 than during P1. Patients with CDI were specifically treated with vancomycin or metronidazole earlier during P2 and P3 than patients from P1 (0.5 +/- 0.5days and 1.0 +/- 1.8days vs. 2.0 +/- 1.7days). The empirical therapy among patients without CDI decreased from 13.6% during P1 to 6.4% during P2 and 5.6% during P3. A rapid CDI diagnosis impacts positively on patient care.