We aimed to rigorously evaluate the impact of prospective audit and feedback on broad-spectrum antimicrobial use among critical care patients.

Prospective, controlled interrupted time series.

Single tertiary care center with 3 intensive care units.

A formal review of all critical care patients on their third or tenth day of broad-spectrum antibiotic therapy was conducted, and suggestions for antimicrobial optimization were communicated to the critical care team.

The primary outcome was broad-spectrum antibiotic use (days of therapy per 1000 patient-days; secondary outcomes included overall antibiotic use, gram-negative bacterial susceptibility, nosocomial Clostridium difficile infections, length of stay, and mortality.

The mean monthly broad-spectrum antibiotic use decreased from 644 days of therapy per 1,000 patient-days in the preintervention period to 503 days of therapy per 1,000 patient-days in the postintervention period (P < .0001); time series modeling confirmed an immediate decrease (± standard error) of 119 ± 37.9 days of therapy per 1,000 patient-days (P = .0054). In contrast, no changes were identified in the use of broad-spectrum antibiotics in the control group (nonintervention medical and surgical wards) or in the use of control medications in critical care (stress ulcer prophylaxis). The incidence of nosocomial C. difficile infections decreased from 11 to 6 cases in the study intensive care units, whereas the incidence increased from 87 to 116 cases in the control wards (P = .04). Overall gram-negative susceptibility to meropenem increased in the critical care units. Intensive care unit length of stay and mortality did not change.

Institution of a formal prospective audit and feedback program appears to be a safe and effective means to improve broad-spectrum antimicrobial use in critical care.

To assess the effect of enhanced infection control measures with screening for gastrointestinal colonization on limiting the spread of carbapenem-resistant Klebsiella pneumoniae in a New York City hospital endemic for this pathogen.

Retrospective observational study with pre- and postinterventional phases.

Beginning in 2006, a comprehensive infection control program was instituted in a 10-bed medical and surgical intensive care unit at a university-based medical center. In addition to being placed in contact isolation, all patients colonized or infected with carbapenem-resistant gram-negative bacilli, vancomycin-resistant Enterococcus, or methicillin-resistant Staphylococcus aureus were cohorted to one end of the unit. Improved decontamination of hands and environmental surfaces was encouraged. In addition, routine rectal surveillance cultures were screened for the presence of carbapenem-resistant pathogens. The number of patients per quarter with clinical cultures positive for carbapenem-resistant K. pneumoniae was compared during the approximately 2-year periods before and after the intervention.

The mean number ( ± SD) of new patients per 1,000 patient-days per quarter with cultures yielding carbapenem-resistant K. pneumoniae decreased from 9.7 ± 2.2 before the intervention to 3.7 ± 1.6 after the intervention (P< .001 ). There was no change in the mean number of patient-days or the mean number of patients per quarter with cultures yielding methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, or carbapenem-resistant Acinetobacter baumannii or Pseudomonas aeruginosa after the intervention. There was no association between antibiotic usage patterns and carbapenem-resistant K. pneumoniae.

The comprehensive intervention that combined intensified infection control measures with routine rectal surveillance cultures was helpful in reducing the incidence of carbapenem-resistant K. pneumoniae in an intensive care unit where strains producing the carbapenemase KPC were endemic.

Multidrug-resistant (MDR) gram-negative bacilli are important nosocomial pathogens.

To determine the incidence of transmission of MDR Acinetobacter baumannii and Pseudomonas aeruginosa from patients to healthcare workers (HCWs) during routine patient care.

Prospective cohort study.

Medical and surgical intensive care units.

We observed HCWs who entered the rooms of patients colonized with MDR A. baumannii or colonized with both MDR A. baumannii and MDR P. aeruginosa. We examined their hands before room entry, their disposable gloves and/or gowns upon completion of patient care, and their hands after removal of gloves and/or gowns and before hand hygiene.

Sixty-five interactions occurred with patients colonized with MDR A. baumannii and 134 with patients colonized with both MDR A. baumannii and MDR P. aeruginosa. Of 199 interactions between HCWs and patients colonized with MDR A. baumannii, 77 (38.7% [95% confidence interval {CI}, 31.9%–45.5%]) resulted in HCW contamination of gloves and/or gowns, and 9 (4.5% [95% CI, 1.6%–7.4%]) resulted in contamination of HCW hands after glove removal before hand hygiene. Of 134 interactions with patients colonized with MDR P. aeruginosa, 11 (8.2% [95% CI, 3.6%–12.9%]) resulted in HCW contamination of gloves and/or gowns, and 1 resulted in HCW contamination of hands. Independent risk factors for contamination with MDR A. baumannii were manipulation of wound dressing (adjusted odds ratio [aQR], 25.9 [95% CI, 3.1–208.8]), manipulation of artificial airway (aOR, 2.1 [95% CI, 1.1–4.0]), time in room longer than 5 minutes (aOR, 4.3 [95% CI, 2.0–9.1]), being a physician or nurse practitioner (aOR, 7.4 [95% CI, 1.6–35.2]), and being a nurse (aOR, 2.3 [95% CI, 1.1–4.8]).

Gowns, gloves, and unwashed hands of HCWs were frequently contaminated with MDR A. baumannii. MDR A. baumannii appears to be more easily transmitted than MDR P. aeruginosa and perhaps more easily transmitted than previously studied methicillin-resistant Staphylococcus aureus or vancomycin-resistant Enterococcus. This ease of transmission may help explain the emergence of MDR A. baumannii.

To characterize the epidemiology of severe (ie, nonsuperficial) surgical site infection (SSI) in community hospitals.

SSI data were collected prospectively at 26 community hospitals in the southeastern United States. Two analyses were performed: (1) a study of the overall prevalence rates of SSI and the prevalence rates of SSI due to specific pathogens in 2005 at all participating hospitals and (2) a prospective study of consecutive surgical procedures at 9 of the 26 community hospitals from 2000 through 2005.

In 2005, a total of 1,010 SSIs occurred after 89,302 procedures (prevalence rate, 1.13 infections per 100 procedures). Methicillin-resistant S. aureus (MRSA) was the pathogen most commonly recovered (from 175 SSIs). Trend data from 2000 through 2005 demonstrated that the prevalence rate of MRSA SSI almost doubled during this period, increasing from 0.12 infections per 100 procedures (95% confidence interval [CI], 0.12-0.13) to 0.23 infections per 100 procedures (95% CI, 0.22-0.24) (P<.0001). In adjusted analysis, MRSA SSI was significantly more prevalent at the end of the study period than at the beginning (prevalence rate ratio, 1.48 [95% CI, 1.36-1.61]; P<.0001).

MRSA was the pathogen that most commonly caused SSI in our network of community hospitals during 2005. The prevalence of MRSA SSI has increased significantly over the past 6 years.

Comorbid conditions have complicated previous analyses of the consequences of methicillin resistance for costs and outcomes of Staphylococcus aureus bacteremia. We compared costs and outcomes of methicillin resistance in patients with S. aureus bacteremia and a single chronic condition.

We conducted a prospective cohort study of hemodialysis-dependent patients with end-stage renal disease and S. aureus bacteremia hospitalized between July 1996 and August 2001. We used propensity scores to reduce bias when comparing patients with methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) S. aureus bacteremia. Outcome measures were resource use, direct medical costs, and clinical outcomes at 12 weeks after initial hospitalization.

Fifty-four patients (37.8%) had MRSA and 89 patients (62.2%) had MSSA. Compared with patients with MSSA bacteremia, patients with MRSA bacteremia were more likely to have acquired the infection while hospitalized for another condition (27.8% vs 12.4%; P = .02). To attribute all inpatient costs to S. aureus bacteremia, we limited the analysis to 105 patients admitted for suspected S. aureus bacteremia from a community setting. Adjusted costs were higher for MRSA bacteremia for the initial hospitalization ($21,251 vs $13,978; P = .012) and after 12 weeks ($25,518 vs $17,354; P = .015). At 12 weeks, patients with MRSA bacteremia were more likely to die (adjusted odds ratio, 5.4; 95% confidence interval, 1.5 to 18.7) than were patients with MSSA bacteremia.

Community-dwelling, hemodialysis-dependent patients hospitalized with MRSA bacteremia face a higher mortality risk, longer hospital stays, and higher inpatient costs than do patients with MSSA bacteremia.

To describe the investigation and management of an outbreak due to multiresistant Acinetobacter baumannii and to determine risk factors for acquisition of the organism.

A 14-bed regional burn unit in a Canadian tertiary-care teaching hospital.

Case-control study with multivariate analysis of potential risk factors using logistic regression analysis. Surveillance cultures were obtained from the hospital environment, from noninfected patients, and from healthcare providers.

A total of 31 (13%) of 247 patients with acute burn injuries acquired multiresistant A. baumannii between December 1998 and March 2000; 18 (58%) of the patients were infected. The organism was recovered from the hospital environment and the hands of healthcare providers. Significant risk factors for acquisition of multiresistant A. baumannii were receipt of blood products (odds ratio [OR], 10.8; 95% confidence interval [CI95], 3.4 to 34.4; P < .001); procedures performed in the hydrotherapy room (OR, 4.1; CI95, 1.3 to 13.1; P = .02); and increased duration of mechanical ventilation (OR, 1.1 per day; CI95, 1.0 to 1.1; P=. 02).

Improved compliance with hand hygiene, strict patient isolation, meticulous environmental cleaning, and temporary closure of the unit to new admissions.

Acquisition of multiresistant A. baumannii was likely multifactorial, related to environmental contamination and contact with transiently colonized healthcare providers. Control measures addressing these potential sources of multiresistant A. baumannii were successful in terminating the outbreak. Ongoing surveillance and continued attention to hand hygiene and adequate environmental cleaning are essential to prevent recurrent outbreaks due to antibiotic-resistant bacteria in burn units.

To evaluate common hand hygiene methods for efficacy in removing Clostridium difficik.

Randomized crossover comparison among 10 volunteers with hands experimentally contaminated by nontoxigenic C. difficile.

Interventions included warm water with plain soap, cold water with plain soap, warm water with antibacterial soap, antiseptic hand wipes, alcohol-based handrub, and a control involving no Intervention. All interventions were evaluated for mean reduction in colony-forming units (CFUs) under 2 contamination protocols: “whole hand” and “palmar surface.” Results were analyzed according to a Bayesian approach, by using hierarchical models adjusted for multiple observations.

Under the whole-hand protocol, the greatest adjusted mean reductions were achieved by warm water with plain soap (2.14 log10 CFU/mL [95% credible interval (Cri), 1.74-2.54 log10 CFU/mL]), cold water with plain soap (1.88 log10 CFU/mL [95% Cri, 1.48-2.28 log10 CFU/mL), and warm water with antibacterial soap (1.51 log10 CFU/mL [95% Cri, 1.12-1.91 logu, CFU/mL]), followed by antiseptic hand wipes (0.57 log10 CFU/mL [95% Cri, 0.17-0.96 log10 CFU/mL]). Alcohol-based handrub (0.06 log10 CFU/mL [95% CrI, -0.34 to 0.45 log10 CFU/mL]) was equivalent to no Intervention. Under the palmar surface protocol, warm water with plain soap, cold water with plain soap, and warm water with antibacterial soap again yielded the greatest mean reductions, followed by antiseptic hand wipes (26.6, 26.6, 26.6, and 21.9 CFUs per plate, respectively), when compared with alcohol-based handrub. Hypothenar (odds ratio, 10.98 [95% Cri, 1.96-37.65]) and thenar (odds ratio, 6.99 [95% Cri, 1.25-23.41]) surfaces were more likely than fingertips to remain heavily contaminated after handwashing.

Handwashing with soap and water showed the greatest efficacy in removing C. difficile and should be performed preferentially over the use of alcohol-based handrubs when contact with C. difficile is suspected or likely.

To investigate the impact of antimicrobial resistance on clinical and economic outcomes among hospitalized patients with multidrug-resistant (MDR) Acinetobacter baumannii bacteremia.

A retrospective, matched-cohort study.

A tertiary care university teaching hospital

A matched case-control (1:1) study was conducted to compare the differences in clinical and economic outcomes of patients with MDR A. baumannii bacteremia and patients with non-MDR A. baumannii bacteremia. Case patients were matched to control patients on the basis of sex, age, severity of underlying and acute illness, and length of hospital stay before onset of bacteremia.

Forty-six (95.8%) of 48 cases with MDR A. baumannii bacteremia were eligible for the study and matched with appropriate controls. The sepsis-related mortality rate was 34.8% among cases and 13.0% among controls, for an attributable mortality rate of 21.8% (adjusted odds ratio, 4.1 [95% confidence interval, 1.1-15.7]; P = .036). After the onset of bacteremia, cases and controls had a significantly different length of hospital stay (54.2 vs 34.1 days; P = .006), hospitalization cost (US$9,349 vs US$4,865; P = .001 ), and antibiotic therapy cost (US$2,257 vs US$1,610; P = .014). Thus, bacteremia due to MDR A. baumannii resulted in 13.4 days of additional hospitalization and US$3,758 of additional costs, compared with bacteremia due to non-MDR A. baumannii.

Patients with MDR A. baumannii bacteremia had a higher mortality rate and incurred greater medical costs than patients with non-MDR A. baumannii bacteremia.

To assess the effectiveness of selective digestive decontamination (SDD) for eradicating carbapenem-resistant Klebsiella pneumoniae (CRKP) oropharyngeal and gastrointestinal carriage.

A randomized, double-blind, placebo-controlled trial with 7 weeks of follow-up per patient.

A 1,000-bed tertiary-care university hospital.

Adults with CRKP-positive rectal swab cultures.

Patients were blindly randomized (1:1) over a 20-month period. The SDD arm received oral gentamicin and polymyxin E gel (0.5 g 4 times per day) and oral solutions of gentamicin (80 mg 4 times per day) and polymyxin E (1 × 106 units 4 times per day for 7 days). The placebo arm received oral placebo gel 4 times per day and 2 placebo oral solutions 4 times per day for 7 days. Strict contact precautions were applied. Samples obtained from the throat, groin, and urine were also cultured.

Forty patients (mean age ± standard deviation, 71 ± 16 years; 65% male) were included. At screening, greater than or equal to 30% of oropharyngeal, greater than or equal to 60% of skin, and greater than or equal to 35% of urine cultures yielded CRKP isolates. All throat cultures became negative in the SDD arm after 3 days (P< .0001). The percentages of rectal cultures that were positive for CRKP were significandy reduced at 2 weeks. At that time, 16.1% of rectal cultures in the placebo arm and 61.1% in the SDD arm were negative (odds ratio, 0.13; 95% confidence interval, 0.02–0.74; P<.0016). A difference between the percentages in the 2 arms was still maintained at 6 weeks (33.3% vs 58.5%). Groin colonization prevalence did not change in either arm, and the prevalence of urine colonization increased in the placebo arm.

This SDD regimen could be a suitable decolonization therapy for selected patients colonized with CRKP, such as transplant recipients or immunocompromised patients pending chemotherapy and patients who require major intestinal or oropharyngeal surgery. Moreover, in outbreaks caused by CRKP infections that are uncontrolled by routine infection control measures, SDD could provide additional infection containment.

Infect Control Hosp Epidemiol 2012;33(1):14-19

Controlled studies that took place in medical intensive care units (MICUs) have demonstrated that bathing patients with Chlorhexidine gluconate (CHG) can reduce skin colonization with potential pathogens and can lessen the risk of central venous catheter (CVC)-associated bloodstream infection (BSI).

TO examine, without oversight of practice by research study staff, the effectiveness or real-world effect of patient cleansing with CHG on rates of CVC-associated BSI.

In the fall of 2005, the MICU at Rush University Medical Center discontinued bathing patients daily with soap and water and substituted skin cleansing with no-rinse, 2% CHG-impregnated cloths. This change was a clinical management decision without research input.

A 21-bed MICU at Rush University Medical Center.

Patients hospitalized in the MICU during the period from September 2004 through October 2006.

In a pre-post study design, we gathered data from administrative and laboratory databases, infection control practitioner logs, and patient medical charts to compare rates of CVC-associated BSI and blood culture contamination between the baseline soap-and-water bathing period (September 2004-October 2005) and the CHG bathing period (November 2005-October 2006). Rates of secondary BSI, Clostridium difficile infection (CDI), ventilator-associated pneumonia (VAP), and urinary tract infection (UTI) served as control variables that were not expected to be affected by CHG bathing.

Bathing with CHG was associated with a statistically significant decrease in the rate of CVC-associated BSI (from 5.31 to 0.69 cases per 1,000 CVC-days; P = .006) and in the rate of blood culture contamination (from 6.99 to 4.1 cases per 1,000 patient-days; P = .04). Rates of secondary BSI, CDI, VAP, and UTI did not change significantly.

In our analysis of real-world practice, daily bathing of MICU patients with CHG was effective at reducing rates of CVC-associated BSI and blood culture contamination. Controlled studies are needed to determine whether these beneficial effects extend outside the MICU.

To review and summarize the status of diagnosis, epidemiology, infection control, and treatment of Clostridium difficile -associated disease (CDAD).

A case definition of CDAD should include the presence of symptoms (usually diarrhea) and at least one of the following positive tests: endoscopy revealing pseudomembranes, stool cytotoxicity test for toxin B, stool enzyme immunoassay for toxin A or B, or stool culture for C difficile (preferably with confirmation of organism toxicity if a direct stool toxin test is negative or not done). Testing of asymptomatic patients, including those who are asymptomatic after treatment, is not recommended other than for epidemiologic purposes. Lower gastrointestinal endoscopy is the only diagnostic test for pseudomembranous colitis, but it is expensive, invasive, and insensitive (51% to 55%) for the diagnosis of CDAD. Stool culture is the most sensitive laboratory test currently in clinical use, but it is not as specific as the cell cytotoxicity assay.

C difficile is the most frequently identified cause of nosocomial diarrhea. The majority of C difficile infections are acquired nosocomially, and most patients remain asymptomatic following acquisition. Antimicrobial exposure is the greatest risk factor for patients, especially clindamycin, cephalosporins, and penicillins, although virtually every antimicrobial has been implicated. Cases of CDAD unassociated with prior antimicrobial or antineoplastic use are very rare. Hands of personnel, as well as a variety of environmental sites within institutions, have been found to be contaminated with C difficile, which can persist as spores for many months. Contaminated commodes, bathing tubs, and electronic thermometers have been implicated as sources of C difficile. Symptomatic and asymptomatic infected patients are the major reservoirs and sources for environmental contamination. Both genotypic and phenotypic typing systems for C difficile are available and have enhanced epidemiologic investigation greatly.

Successful infection control measures designed to prevent horizontal transmission include the use of gloves in handling body substances and replacement of electronic thermometers with disposable devices. Isolation, cohorting, handwashing, environmental disinfection, and treatment of asymptomatic carriers are recommended practices for which convincing data of efficacy are not available. The most successful control measure directed at reduction in symptomatic disease has been antimicrobial restriction.

Treatment of symptomatic (but not asymptomatic) patients with metronidazole or vancomycin for 10 days is effective; metronidazole may be preferred to reduce risk of vancomycin resistance among other organisms in hospitals. Recurrence of symptoms occurs in 7% to 20% of patients and is due to both relapse and reinfection. Over 90% of first recurrences can be treated successfully in the same manner as initial cases. Combination treatment with vancomycin plus rifampin or the addition orally of the yeast Saccharomyces boulardii to vancomycin or metronidazole treatment has been shown to prevent subsequent diarrhea in patients with recurrent disease.

To determine risk factors for bloodstream infections (BSIs) caused by Klebsiella pneumoniae producing metallo-β-lactamases (MBLs) or K. pneumoniae carbapenemases (KPCs), as well as risk factors for mortality associated with carbapenem-resistant K. pneumoniae, among intensive care unit (ICU) patients.

Two case-control studies were conducted in a patient cohort with K. pneumoniae BSIs in an 8-bed ICU in a Greek hospital from January 1, 2007, through December 31, 2008. In study 1, patients with K. pneumoniae BSIs were allocated among 3 groups according to isolate susceptibility profile: (1) carbapenem-susceptible insolates (control group), (2) MBL-producing isolates, or (3) KPC-producing isolates. The MBL and KPC groups were compared with the control group to identify risk factors for development of K. pneumoniae BSI. In study 2, patients with K. pneumoniae BSIs who died were compared with survivors to identify risk factors for mortality.

Fifty-nine patients had K. pneumoniae BSIs (22 with carbapenem-susceptible isolates, 18 with MBL-producing isolates, and 19 with KPC-producing isolates). All KPC-producing isolates carried the blaKPC-2 gene, and 17 of 18 MBL-producing isolates carried blaVIM-1 Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.13 [95% confidence interval, 1.03–1.25]; P = .02) was independently associated with KPC-producing K. pneumoniae BSIs. Nine (41%) of 22 control patients, 8 (44%) of 18 MBL group patients, and 13 (68%) of 19 KPC group patients died in the ICU. Nine (41%) of 22 control patients, 10 (56%) of 18 MBL group patients, and 15 (79%) of 19 KPC group patients died in the hospital. Isolation of KPC-producing K. pneumoniae was an independent predictor of ICU death (P = .04) and in-hospital death (P = .03) but not infection-attributable death.

BSIs due to KPC-producing K. pneumoniae resulted in significantly increased mortality. The accurate and rapid detection of these pathogens is necessary for therapeutic considerations and for the implementation of infection control measures to contain them.