An evaluation of toxigenic positivity as a patient outcome metric of antimicrobial stewardship in Saudi Arabia.

Background: Antimicrobial stewardship has been associated with a reduction in the incidence of healthcare-associated infection (HA-CDI). However, CDI remains under-recognised in many low and middle-income countries where clinical and surveillance resources required to identify HA-CDI are often lacking. The rate of toxigenic stool positivity in the stool of hospitalised patients may offer an alternative metric for these settings, but its utility remains largely untested.

Aim/objective: To examine the impact of antimicrobial stewardship on the rate of toxigenic positivity among hospitalised patients presenting with diarrhea.

Methods: A 12-year retrospective review of laboratory data was conducted to compare the rates of toxigenic in diarrhoea stool of patients in a hospital in Saudi Arabia, before and after implementation of an antimicrobial stewardship programme.

Result: There was a significant decline in the rate of toxigenic positivity from 9.8 to 7.4% following the implementation of the antimicrobial stewardship programme, and a reversal of a rising trend.

Discussion: The rate of toxigenic positivity may be a useful patient outcome metric for evaluating the long-term impact of antimicrobial stewardship on CDI, especially in settings with limited surveillance resources. The accuracy of this metric is, however, dependent on the avoidance of arbitrary repeated testing of a patient for cure, and testing only unformed or diarrhoea stool specimens. Further studies are required within and beyond Saudi Arabia to examine the utility of this metric.