Implementation of Polymerase Chain Reaction to Rule Out Clostridium difficile Infection Is Associated With Reduced Empiric Antibiotic Duration of Therapy.

PURPOSE

The polymerase chain reaction (PCR) test has higher sensitivity and a faster turnaround time than the enzyme immunoassay (EIA) for identification of Clostridium difficile, although the clinical implications of these variables are not well described.

METHODS

Inpatients with a negative EIA (n = 79) or PCR (n = 87) test were retrospectively evaluated. Patients were excluded if they had a positive EIA or PCR test during the same hospitalization or if they were currently receiving treatment for C. difficile infection (CDI) prior to admission. The primary outcome was empiric CDI antibiotic duration of therapy associated with each test method.

RESULTS

Empiric CDI antibiotic duration of therapy was 2.31 (95% confidence interval [CI], 1.48-3.15) days for the EIA group and 0.88 (0.45-1.33) days for the PCR group (P = .007). Number of diagnostic laboratory tests performed per patient were 2.73 (2.64-2.83) and 1.16 (1.04-1.28) tests, respectively (P < .001).

CONCLUSION

Use of the PCR test to rule out CDI was associated with reduced duration of empiric CDI antibiotic therapy and fewer diagnostic laboratory tests performed per patient. When combined with fewer diagnostic laboratory tests performed per patient and shorter duration of contact isolation, the higher acquisition cost of the PCR test was offset, resulting in cost neutrality. These findings provide additional data to support the routine use of the PCR test.