Thermoregulation and risk of surgical site infection.

Surgical site infections (SSIs) occur in approximately 2%-5% of patients undergoing surgery in the acute care setting in the United States. These infections result in increased length of stay, higher risk of death, and increased cost of care compared with that in uninfected surgical patients. Given the inclusion of maintenance of perioperative normothermia for all major surgeries as a means of lowering the risk of infection in the Surgical Care Improvement Project 2009, we prepared a summary of the literature to determine the strength and quantity of the evidence underlying the performance measure. Although the data are generally supportive of perioperative normothermia as a means of reducing the risk of SSIs, a more rigorous approach using standard SSI definitions as well as standardized temperature measurements (and timing thereof) will further delineate the role played by temperature regulation in SSI development.

Use of vaporized hydrogen peroxide decontamination during an outbreak of multidrug-resistant Acinetobacter baumannii infection at a long-term acute care hospital.

OBJECTIVES: To describe vaporized hydrogen peroxide (VHP) as an adjuvant in the control of multidrug-resistant (MDR) Acinetobacter baumannii infection in a long-term acute care hospital (LTACH) and to describe the risk factors for acquisition of MDR A. baumannii infection in the LTACH population. DESIGN: Outbreak investigation, case-control study, and before-after intervention trial. SETTING: A 54-bed LTACH affiliated with a tertiary care center in northeastern Ohio. METHODS: Investigation of outbreak with clinical and environmental cultures, antimicrobial susceptibility testing, polymerase chain reaction assay of repetitive chromosomal elements to type strains, and case-control study; and intervention consisting of comprehensive infection control measures and VHP environmental decontamination. RESULTS: Thirteen patients infected or colonized with MDR A. baumannii were identified from January 2008 through June 2008. By susceptibility testing, 10 (77%) of the 13 isolates were carbapenem-resistant. MDR A. baumannii was found in wound samples, blood, sputum, and urine. Wounds were identified as a risk factor for MDR A. baumannii colonization. Ventilator-associated pneumonia was the most common clinical syndrome caused by the pathogen, and the associated mortality was 14% (2 of the 13 case patients died). MDR A. baumannii was found in 8 of 93 environmental samples, including patient rooms and a wound care cart; environmental and clinical cultures were genetically related. Environmental cultures were negative immediately after VHP decontamination and both 24 hours and 1 week after VHP decontamination. Nosocomial acquisition of the pathogen in the LTACH ceased after VHP intervention. When patients colonized with MDR A. baumannii reoccupied rooms, environmental contamination recurred. CONCLUSION: Environmental decontamination using VHP combined with comprehensive infection control measures interrupted nosocomial transmission of MDR A. baumannii in an LTACH. The application of this novel approach to halt the transmission of MDR A. baumannii warrants further investigation.

Modulation of cell wall structure and antimicrobial susceptibility by a Staphylococcus aureus eukaryote-like serine/threonine kinase and phosphatase.

It is well established that prokaryotes and eukaryotes alike utilize phosphotransfer to regulate cellular functions. One method by which this occurs is via eukaryote-like serine/threonine kinase (ESTK)- and phosphatase (ESTP)-regulated pathways. The role of these enzymes in Staphylococcus aureus has not yet been examined. This resilient organism is a common cause of hospital-acquired and community-associated infections, infecting immunocompromised and immunocompetent hosts alike. In this study, we have characterized a major functional ESTK (STK) and ESTP (STP) in S. aureus and found them to be critical modulators of cell wall structure and susceptibility to cell wall-acting beta-lactam antibiotics. By utilizing gene knockout strategies, we created S. aureus N315 mutants lacking STP and/or STK. The strain lacking both STP and STK displayed notable cell division defects, including multiple and incomplete septa, bulging, and irregular cell size, as observed by transmission electron microscopy. Mutants lacking STP alone displayed thickened cell walls and increased resistance to the peptidoglycan-targeting glycylglycine endopeptidase lysostaphin, compared to the wild type. Additionally, mutant strains lacking STK or both STK and STP displayed increased sensitivity to cell wall-acting cephalosporin and carbapenem antibiotics. Together, these results indicate that S. aureus STK- and STP-mediated reversible phosphorylation reactions play a critical role in proper cell wall architecture, and thus the modulation of antimicrobial resistance, in S. aureus.