Surbhi Leekha

General Principles of Antimicrobial Therapy

Antimicrobial agents are some of the most widely, and often injudiciously, used therapeutic drugs worldwide. Important considerations when prescribing antimicrobial therapy include obtaining an accurate diagnosis of infection; understanding the difference between empiric and definitive therapy; identifying opportunities to switch to narrow-spectrum, cost-effective oral agents for the shortest duration necessary; understanding drug characteristics that are peculiar to antimicrobial agents (such as pharmacodynamics and efficacy at the site of infection); accounting for host characteristics that influence antimicrobial activity; and in turn, recognizing the adverse effects of antimicrobial agents on the host. It is also important to understand the importance of antimicrobial stewardship, to know when to consult infectious disease specialists for guidance, and to be able to identify situations when antimicrobial therapy is not needed. By following these general principles, all practicing physicians should be able to use antimicrobial agents in a responsible manner that benefits both the individual patient and the community.

Transfer of multidrug-resistant bacteria to healthcare workers' gloves and gowns after patient contact increases with environmental contamination.

Objective:To assess the role of environmental contamination in the transmission of multidrug-resistant bacteria to healthcare workers’ clothing. Design:Prospective cohort. Setting:Six intensive care units at a tertiary care hospital. Subjects:Healthcare workers including registered nurses, patient care technicians, respiratory therapists, occupational/physical therapists, and physicians. Interventions:None. Measurements and Main Results:One hundred twenty of 585 (20.5%) healthcare worker/patient interactions resulted in contamination of healthcare workers’ gloves or gowns. Multidrug-resistant Acinetobacter baumannii contamination occurred most frequently, 55 of 167 observations (32.9%; 95% confidence interval [CI] 25.8% to 40.0%), followed by multidrug-resistant Pseudomonas aeruginosa, 15 of 86 (17.4%; 95% CI 9.4% to 25.4%), vancomycin-resistant Enterococcus, 25 of 180 (13.9%, 95% CI 8.9, 18.9%) and methicillin-resistant Staphylococcus aureus, 21 of 152 (13.8%; 95% CI 8.3% to 19.2%). Independent risk factors associated with healthcare worker contamination with multidrug-resistant bacteria were positive environmental cultures (odds ratio [OR] 4.2; 95% CI 2.7–6.5), duration in room for >5 mins (OR 2.0; 95% CI 1.2–3.4), performing physical examinations (OR 1.7; 95% CI 1.1–2.8), and contact with the ventilator (OR 1.8; 95% CI, 1.1–2.8). Pulsed field gel electrophoresis determined that 91% of healthcare worker isolates were related to an environmental or patient isolate. Conclusions:The contamination of healthcare workers’ protective clothing during routine care of patients with multidrug-resistant organisms is most frequent with A. baumannii. Environmental contamination was the major determinant of transmission to healthcare workers’ gloves or gowns. Compliance with contact precautions and more aggressive environmental cleaning may decrease transmission.

Seasonality of staphylococcal infections

Characterization of seasonal variation of Staphylococcus aureus is important in understanding the epidemiology of, and designing preventive strategies against this highly virulent and ever-evolving pathogen. In this review, we summarize the findings of epidemiological studies that have evaluated seasonality in S. aureus colonization and infection. Although most studies published to date are methodologically weak, some seasonal variation in the occurrence of S. aureus infection appears to exist, particularly an association of warm-weather months with S. aureus skin and soft-tissue infections. We highlight the limitations of the published literature, and provide suggestions for future studies on this topic.

Relevance of Influenza A Virus Detection by PCR, Shell Vial Assay, and Tube Cell Culture to Rapid Reporting Procedures

ABSTRACT Influenza A virus was detected at higher rates and for more extended time periods with real-time PCR than with cell cultures. We show here that, using the theranostic approach, rapid viral detection and reporting can provide for early implementation and assessment of available antiviral therapy.

Healthcare Personnel Attire in Non-Operating-Room Settings

Healthcare personnel (HCP) attire is an aspect of the medical profession steeped in culture and tradition. The role of attire in cross-transmission remains poorly established, and until more definitive information exists priority should be placed on evidence-based measures to prevent healthcare-associated infections (HAIs). This article aims to provide general guidance to the medical community regarding HCP attire outside the operating room. In addition to the initial guidance statement, the article has 3 major components: (1) a review and interpretation of the medical literature regarding (a) perceptions of HCP attire (from both HCP and patients) and (b) evidence for contamination of attire and its potential contribution to cross-transmission; (2) a review of hospital policies related to HCP attire, as submitted by members of the Society for Healthcare Epidemiology of America (SHEA) Guidelines Committee; and (3) a survey of SHEA and SHEA Research Network members that assessed both institutional HCP attire policies and perceptions of HCP attire in the cross-transmission of pathogens. Recommendations for HCP attire should attempt to balance professional appearance, comfort, and practicality with the potential role of apparel in the cross-transmission of pathogens. Although the optimal choice of HCP attire for inpatient care remains undefined, we provide recommendations on the use of white coats, neckties, footwear, the bare-below-the-elbows strategy, and laundering. Institutions considering these optional measures should introduce them with a well-organized communication and education effort directed at both HCP and patients. Appropriately designed studies are needed to better define the relationship between HCP attire and HAIs.

Rapid Testing Using the Verigene Gram-Negative Blood Culture Nucleic Acid Test in Combination with Antimicrobial Stewardship Intervention against Gram-Negative Bacteremia

ABSTRACT Rapid identification of microorganisms and antimicrobial resistance is paramount for targeted treatment in serious bloodstream infections (BSI). The Verigene Gram-negative blood culture nucleic acid test (BC-GN) is a multiplex, automated molecular diagnostic test for identification of eight Gram-negative (GN) organisms and resistance markers from blood culture with a turnaround time of approximately 2 h. Clinical isolates from adult patients at the University Maryland Medical Center with GN bacteremia from 1 January 2012 to 30 June 2012 were included in this study. Blood culture bottles were spiked with clinical isolates, allowed to incubate, and processed by BC-GN. A diagnostic evaluation was performed. In addition, a theoretical evaluation of time to effective and optimal antibiotic was performed, comparing actual antibiotic administration times from chart review (“control”) to theoretical administration times based on BC-GN reporting and antimicrobial stewardship team (AST) review (“intervention”). For organisms detected by the assay, BC-GN correctly identified 95.6% (131/137), with a sensitivity of 97.1% (95% confidence interval [CI], 90.7 to 98.4%) and a specificity of 99.5% (95% CI, 98.8 to 99.8%). CTX-M and OXA resistance determinants were both detected. Allowing 12 h from Gram stain for antibiotic implementation, the intervention group had a significantly shorter duration to both effective (3.3 versus 7.0 h; P < 0.01) and optimal (23.5 versus 41.8 h; P < 0.01) antibiotic therapy. BC-GN with AST intervention can potentially decrease time to both effective and optimal antibiotic therapy in GN BSI.

Should National Standards for Reporting Surgical Site Infections Distinguish between Primary and Revision Orthopedic Surgeries

OBJECTIVE To compare the surgical site infection (SSI) rate after primary total hip arthroplasty with the SSI rate after revision total hip arthroplasty. DESIGN Retrospective cohort study. SETTING Mayo Clinic in Rochester, Minnesota, a referral orthopedic center. PATIENTS All patients undergoing primary total hip arthroplasty or revision total hip arthroplasty during the period from January 1, 2002, through December 31, 2006. METHODS We obtained data on total hip arthroplasties from a prospectively maintained institutional surgical database. We reviewed data on SSIs collected prospectively as part of routine infection control surveillance, using the criteria of the Centers for Disease Control and Prevention for the definition of an SSI. We used logistic regression analyses to evaluate differences between the SSI rate after primary total hip arthroplasty and the SSI rate after revision total hip arthroplasty. RESULTS A total of 5,696 total hip arthroplasties (with type 1 wound classification) were analyzed, of which 1,381 (24%) were revisions. A total of 61 SSIs occurred, resulting in an overall SSI rate of 1.1% for all total hip arthroplasties. When stratified by the National Nosocomial Infection Surveillance (NNIS) risk index, SSI rates were 0.5%, 1.2%, and 1.6% in risk categories 0, 1, and 2, respectively. After controlling for the NNIS risk index, the risk of SSI after revision total hip arthroplasty was twice as high as that after primary total hip arthroplasty (odds ratio, 2.2 [95% confidence interval, 1.3-3.7]). In the analysis restricted to the development of deep incisional or organ space infections, the risk of SSI after revision total hip arthroplasty was nearly 4 times that after primary total hip arthroplasty (odds ratio, 3.9 [95% confidence interval, 2.0-7.6]). CONCLUSION Including revision surgeries in the calculation of SSI rates can result in higher infection rates for institutions that perform a larger number of revisions. Taking NNIS risk indices into account does not eliminate this effect. Differences between primary and revision surgeries should be considered in national standards for the reporting of SSIs.

Epidemiology and Control of Pertussis Outbreaks in a Tertiary Care Center and the Resource Consumption Associated With These Outbreaks

OBJECTIVE To describe the epidemiology and control of 2 separate outbreaks of pertussis at a large tertiary care center and the resource consumption associated with these outbreaks. DESIGN Descriptive study. SETTING The Mayo Clinic in Rochester, Minnesota, a tertiary care center catering to both referral patients and patients from the community. METHODS We reviewed routine and enhanced surveillance data collected by infection prevention and control practitioners during the outbreaks. Pertussis was diagnosed either on the basis of a nasopharyngeal specimen positive for Bordetella pertussis by use of polymerase chain reaction (PCR) or on the basis of a compatible clinical syndrome along with an epidemiologic link to PCR-confirmed cases. RESULTS Two pertussis outbreaks, the first community based and the second hospital based (ie, due to transmission among healthcare personnel), occurred during the period from October 2004 through October 2005. In the first outbreak from November 2004 through March 2005, there were 109 cases diagnosed; 105 (96%) of these cases were diagnosed on the basis of a nasopharyngeal specimen positive for B. pertussis by use of PCR. Adolescents 10-19 years of age were most affected (77 cases [71%]). Only 13 cases (12%) occurred among healthcare personnel; however, many healthcare personnel required postexposure prophylaxis. A second outbreak of 122 cases occurred during the period from July through October 2005; of these 122 cases, 96 (79%) were diagnosed on the basis of a nasopharyngeal specimen positive for B. pertussis by use of PCR, and 64 (52%) involved healthcare personnel. There were many instances of transmission among healthcare personnel and from patients to healthcare personnel, but no documented transmission from healthcare personnel to patients. The outbreaks were controlled by aggressive case finding, treatment of those infected, prophylaxis of all healthcare personnel and patients who had contact with both probable and confirmed cases, implementation of educational efforts, and compliance with respiratory etiquette. Vaccination of healthcare personnel against pertussis began in October 2005. CONCLUSION Pertussis remains a public health problem. Outbreaks in healthcare facilities consume the resources of those facilities in terms of personnel, testing, treatment of cases, and prophylaxis of those individuals who were in contact with those cases. Adult vaccination may reduce the disease burden.

Risk factors for central line-associated bloodstream infections in the era of best practice.

BACKGROUND: Best clinical practice aims to eliminate central line-associated blood stream infections (CLABSIs). However, CLABSIs still occur. This studys aim was to identify risk factors for CLABSI in the era of best practice. METHODS: Critically ill surgical patients admitted over 2 years to the intensive care unit (ICU) for ≥4 days were studied. Patients with CLABSI as cause for ICU admission were excluded. Patients who developed CLABSI (National Healthcare Safety Network definition) were compared with those who did not. Hand hygiene, maximal sterile barriers, chlorhexidine scrub, avoidance of femoral vein, and proper maintenance were emphasized. Variables collected included demographics, diagnosis, and severity of illness using the Acute Physiology and Chronic Health Evaluation (APACHE) IV database and the hospital central data repository. RESULTS: Of 961 patients studied, 51 patients (5.2%) developed 59 CLABSIs. Mean time from ICU admission to CLABSI was 26 days ± 26 days. The CLABSI group was more likely to be male (odds ratio [OR] 1.93, 95% confidence interval [CI] 1.02–3.68), more critically ill on ICU admission (APACHE IV score 85.2 ± 21.9 vs. 65.6 ± 23.2, p < 0.01), more likely admitted to the emergency surgery service (OR 1.92, 95% CI 1.02–3.61), and had an association with reopening of recent laparotomy (OR 2.08, 95% CI 1.10–3.94). CONCLUSION: In the era of best practice, patients who develop CLABSI are clinically distinct from those who do not develop CLABSI. These CLABSIs may be due to deficiencies of the CLABSI definition or represent patient populations requiring enhanced prevention techniques. LEVEL OF EVIDENCE: III, prognostic study.

Isolation Precautions for Visitors

Infection Control & Hospital Epidemiology / FirstView Article / April 2015, pp 1 12 DOI: 10.1017/ice.2015.67, Published online: 10 April 2015 Link to this article: http://journals.cambridge.org/abstract_S0899823X15000677 How to cite this article: L. Silvia Munoz-Price, David B. Banach, Gonzalo Bearman, Jane M. Gould, Surbhi Leekha, Daniel J. Morgan, Tara N. Palmore, Mark E. Rupp, David J. Weber and Timothy L. Wiemken Isolation Precautions for Visitors. Infection Control & Hospital Epidemiology, Available on CJO 2015 doi:10.1017/ice.2015.67 Request Permissions : Click here