AT PAS 2017
SAN FRANCISCO (FRONTLINE MEDICAL NEWS) – Implementation of sample testing using a molecular approach, combined with coordinated and multidisciplinary notification of clinicians, has reduced the time to deliver adequate antibiotic therapy for bacteremia caused by gram-positive cocci including methicillin-resistant Staphylococcus aureus (MRSA) from 60 hours to 4 hours.
“We observed a significant decrease in the time to adequate antibiotics, significant decrease in time to first negative blood culture, and decreased variation in both measures,” Michael Tchou , MD, of the division of hospital medicine at Cincinnati Children’s Hospital Medical Center (CCHMC), reported at the Pediatric Academic Societies meeting.
The traditional clinical pathway for gram-positive cocci-related infections involves the immediate use of empiric antibiotics, followed by a stepwise process that involves growth of the organisms on blood agar, Gram staining, species identification, and determination of the antibiotics that are actually effective. The intervening period between the empiric and potentially inadequate antibiotics and those that are truly effective can be 48 hours or longer.
Speeding up the time to delivery of adequate antibiotics is a must, Dr. Tchou emphasized.
CCHMC initiated the use of a multiplex polymerase chain reaction (PCR)–based identification protocol in mid-2013. Multiplex PCR targets specific regions of genetic material. In the protocol, empiric antibiotics are administered. At the same time, multiplex PCR is done. Blood culture and subsequent Gram staining of the bacteria in the colonies that grow also are done. PCR-based species identification and determination of probable antibiotic resistance, which takes about 3 hours, can be used to shift antibiotic therapy to adequate therapy, which is defined as the necessary antimicrobial therapy, even if it is still too broad. The growth-based results available the next day help fine-tune the therapy.
The use of multiplex PCR speeds the time to an “actionable result” – the time to recognize that the empiric antibiotic therapy is not the best, Dr. Tchou said.
At CCHMC, an actionable result is obtained for about 1 of every 40 cases of bloodstream infection determined to be caused by gram-positive cocci. The delay in switching to adequate antibiotic coverage used to average 60 hours.
In an effort to do better, Dr. Tchou and colleagues set a goal of reducing the time to adequate antibiotic therapy for gram-positive bacteremia from 60 to 12 hours within 6 months.
The effort necessitated the coordinated involvement of a multidisciplinary team, with a rapid system of clinician notification, and the real-time software-based monitoring of results. In the system, an actionable result triggers a text message to the on-call antibiotic stewardship contact, who in turn notifies the primary care team.
The multidisciplinary system was rolled out first for MRSA. The effort was even more successful than they hoped for. Delivery of appropriate antibiotics for MRSA infections dropped from about 60 hours to 13 hours within a few months, with a further decrease to 4 hours within another few months. Roll out of the initiative to all gram-positive cocci including coagulase-negative staphylococci, Streptococcus pyogenes, Enterococcus faecalis, and E. faecium similarly achieved the 4-hour target within months.
And preliminary results not presented by Dr. Tchou indicate an earlier resolution of bacteremia.
Next steps include modifying the decision support software to allow direct paging of providers instead of using text messages, expansion of the antibiotic coverage, and achieving similar improved treatment time for gram-negative bloodstream infections.
The study was sponsored by Cincinnati Children’s Hospital and was not funded. Dr. Tchou reported having no relevant financial disclosures.
