Shutting down the flow of antibiotics stops C. diff infections

January 12th, 2015

There comes a time in infection control when there are enough epidemiological indicators and sufficient risk of patient harm that one must take decisive action, a la public health pioneer John Snow removing the Broad Street water pump handle to end a legendary cholera outbreak in 19^th century London.

In this case the pathogen is Clostridium difficile in 21^st century Seattle. C. diff infections (CDIs) were besetting neurosurgical ICU patients with external ventricular drain (EVDs) on continuously systemic delivery of cefazolin as prophylaxis against infections. Driven by the emergence of the highly virulent NAP1 strain, C. diff kills some 14,000 patients a year in the U.S. The NAP1 strain is often resistant to florquinolones, which are commonly used to treat many other hospital infections. The bigger problem – and the reason C. diff was recently cited as an “urgent threat” by the CDC – is that antibiotic use in general predisposes patients to acquire CDI, which can emerge after the commensal bacteria in the gut have been wiped out by treatment for other infections.

With C. diff causing recurrent infections in neurosurgical patients and threatening other patient groups if infection control measures failed, Timothy H. Dellit, MD, associate medical director at Harborview Medical Center in Seattle, had a decision to make. The epidemiological evidence raised the question of whether the continuous antibiotic prophylaxis was causing C. diff in the patents with EVDS, which are placed as drains to prevent fluid buildup around the brain after surgery. Moreover, in reviewing the literature, Dellit questioned how many infections the prophylaxis was actually preventing.

“We said if there really is not data out there to support the use systemic prophylaxis, and at the same time we may be causing harm with an increased incidence of Clostridium difficile, why don’t we just stop?," he said. "So that’s what we did. We discontinued the use of cefazolin.”

The antibiotic stewardship intervention worked, significantly reducing CDIs without triggering any other infection problems in the EVD patients that had been on cefazolin prophylaxis, Dellit said recently in San Francisco at the IDWeek conference.

For more on this story and some breaking news on antibiotic stewardship see the Dec. 2013 issue of Hospital Infection Control & Prevention.