Antimicrobial Resistance Scan for Sep 01, 2016

CRE cases in Wisconsin
;
ASP intervention in C diff patients

Four CRE cases reported in Wisconsin

Investigators with the Centers for Disease Control and Prevention (CDC) today describe a small cluster of the worrisome "superbug" known as carbapenem-resistant Enterobacteriaceae (CRE) at two Wisconsin hospitals in Morbidity and Mortality Weekly Report (MMWR).

According to the report, officials with the Wisconsin State Laboratory of Hygiene notified the Wisconsin Division of Public Health in June 2015 that five carbapenemase-producing CRE isolates had been identified among four inpatients at two hospitals in southeastern Wisconsin. They all contained the KPC gene, which codes for Klebsiella pneumoniae carbapemenase.

The KPC-CRE isolates were identified among 49 isolates obtained from 46 patients from February to May 2015. The median age of the four patients (two men and two women) was 65, and median hospitalization length was 83 days. All four patients had been intubated and undergone a tracheostomy.

Further investigation revealed that the five isolates exhibited a high degree of genetic relatedness but did not uncover how the bacteria traveled between the two facilities. Active surveillance conducted at the two hospitals in July 2015 identified no further cases. Site visits, reviews of infection prevention protocols, and interviews with infection prevention staff members, primary care providers, and patients found no breaches in recommended practices.

The authors of the report say the findings demonstrate the importance of routine hospital- and laboratory-based surveillance for the detection of healthcare-related CRE. In this case, staff at neither of the two hospitals was aware of the possibility of CRE transmission among their patients. The authors also say the use of molecular subtyping methods (like whole-genome sequencing) to determine the genetic similarities in the isolates was particularly valuable.
Sep 2 MMWR report

ASP intervention not found to improve outcomes in C diff patients

A study today out of the University of Michigan has found a real-time antibiotic stewardship program (ASP) intervention in patients with Clostridium difficile infection (CDI) improved process measures but did not improve outcomes.

The study, published in the American Journal of Infection Control, details the results of what the authors call a "quasiexperimental" study of adult CDI patients before and after a real-time ASP review was initiated.

In the intervention group (285 patients), an ASP pharmacist was called in after diagnosis to review each case with the medical team and make recommendations on optimal treatment, antibiotic therapy and acid-suppressing therapy, and surgical/infectious disease consultation. In the control group (307 patients), CDI treatment was left to the discretion of the patient's primary medical team. Overall, ASP pharmacists provided treatment recommendations for 129 of the 285 patients in the intervention group.

The primary measurement of the study was a composite of several outcomes—including 30-day mortality, intensive care unit admission, surgery, and CDI recurrence. But process measures that may influence outcomes in CDI patients were also measured, with researchers looking at whether acid-suppressive therapy was reduced in CDI patients and whether patients with severe CDI received infectious disease consultation and appropriate and timely antibiotic therapy.

In the end, the researchers found that ASP intervention reduced unnecessary acid-suppressing therapy when compared with the control group. And patients with severe CDI who received ASP intervention were more likely to be treated with vancomycin, receive vancomycin therapy more quickly, and receive infectious disease consultation than the patients in the pre-intervention group. This finding is in line with previous studies on ASP intervention in CDI patients.

However, the investigators were not able to demonstrate a statistically significant improvement in primary clinical outcomes among the patients who received ASP intervention. Occurrence of primary composite outcome was 14.7% in the pre-intervention group and 12.3% in the intervention groups. The authors of the study say this may be due to the low baseline rates of these outcomes among the patients.

In conclusion, the authors say their findings, when added to previous literature on the topic, raise questions about whether ASP involvement in the conventional management of CDI is worthwhile, especially in institutions with low rates of CDI-attributable complications.
Sep 1 Am J Infect Control study

Newsletter Sign-up

Get CIDRAP news and other free newsletters.

Sign up now»

OUR UNDERWRITERS

Unrestricted financial support provided by

Bentson Foundation 3M Gilead 
Grant support for ASP provided by

  Become an underwriter»