One size does not fit all: why universal decolonization strategies to prevent methicillin-resistant Staphylococcus aureus colonization and infection in adult intensive care units may be inappropriate for neonatal intensive care units.

The REDUCE MRSA Trial (Randomized Evaluation of Decolonization vs Universal Clearance to Eliminate Methicillin-Resistant Staphylococcus aureus), a large multicenter, randomized controlled trial in adult intensive care units (ICUs), found universal decolonization to be more effective than surveillance and isolation procedures with or without targeted decolonization for reducing rates of MRSA-positive clinical cultures. The Agency for Healthcare Research and Quality and the Centers for Disease Control and Prevention subsequently published protocols for implementing universal decolonization in ICUs based on the trial's methods. Caution should be exercised before widely adopting these procedures in neonatal intensive care units (NICUs), particularly strategies that involve bathing with chlorhexidine and mupirocin application due to the potential for adverse events in their unique patient population, especially preterm infants. Large multicenter trials in the NICUs are needed to evaluate the efficacy, short- and long-term safety, and cost effectiveness of these strategies prior to their widespread implementation.

Perceptions of hand hygiene practices in China.

Hand hygiene is considered one of the most important infection control measures for preventing healthcare-associated infections. However, compliance rates with recommended hand hygiene practices in hospitals remain low. Previous literature on ways to improve hand hygiene practices has focused on the USA and Europe, whereas studies from developing countries are less common. In this study, we sought to identify common issues and potential strategies for improving hand hygiene practices in hospitals in China. We used a qualitative survey design based on in-depth interviews with 25 key hospital and public health staff in eight hospitals selected by the Chinese Ministry of Health. We found that hospital workers viewed hand hygiene as paramount to effective infection control and had adequate knowledge about proper hand hygiene practices. Despite these positive attitudes and adequate knowledge, critical challenges to improving rates of proper hand hygiene practices were identified. These included lack of needed resources, limited organisational authority of hospital infection control departments, and ineffective use of data monitoring and feedback to motivate improvements. Our study suggests that a pivotal issue for improving hand hygiene practice in China is providing infection control departments adequate attention, priority, and influence within the hospital, with a clear line of authority to senior management. Elevating the place of infection control on the hospital organisational chart and changing the paradigm of surveillance to continuous monitoring and effective data feedback are central to achieving improved hand hygiene practices and quality of care.

Promotion of hand hygiene techniques through use of a surveillance tool.

Effective hand hygiene practice in a clinical healthcare setting is the most effective means to prevent, control and reduce healthcare-associated infections. Despite the introduction of hand hygiene practices and targeted campaigns, surveillance to ensure implementation of these techniques remains limited. Surveillance is widely accepted as an essential component to infection control campaigns. Therefore, we sought to design and test an easy-to-use surveillance instrument for hospital hand hygiene developed and piloted for three months in nine hospitals in China. This paper presents the resulting hand hygiene surveillance instrument as well as explicit guidelines for its implementation.

Comparative antimicrobial activity of gatifloxacin with ciprofloxacin and beta-lactams against gram-positive bacteria.

Gatifloxacin is a new 8-methoxy fluoroquinolone. The in-vitro antibacterial activity of gatifloxacin was compared to that of ciprofloxacin, ceftriaxone, imipenem, piperacillin/tazobactam and amoxicillin/clavulanic acid against 165 streptococcal isolates, 369 staphylococcal isolates, and 50 enterococcal isolates recently recovered from clinical isolates. Gatifloxacin was the most active agent tested against streptococci including penicillin-nonsusceptible Streptococcus pneumoniae (MIC(90) 0.5 microg/mL). Imipenem and gatifloxacin (MIC(90) 0.5 microg/mL) were the most active agents tested against viridans group streptococci. All the agents demonstrated excellent activity against methicillin-susceptible S. aureus. Imipenem, piperacillin/tazobactam, amoxicillin/clavulanic acid, and gatifloxacin had good activity against methicillin-sensitive S. epidermidis. Among the methicillin-sensitive and methicillin-resistant coagulase-negative staphylococci tested, gatifloxacin was the most active agent. Amoxicillin/clavulanic acid and gatifloxacin were the most active agents against E. faecalis. Thus, gatifloxacin possesses equal or superior activity when compared to ciprofloxacin and beta-lactams making it a promising new fluoroquinolone for clinical use in treating Gram-positive infections.

Molecular typing demonstrating transmission of gram-negative rods in a neonatal intensive care unit in the absence of a recognized epidemic.

Molecular typing techniques have been used in outbreak investigations. In this study, molecular typing techniques were used to track the spread of gram-negative rods (GNRs) in a neonatal intensive care unit (NICU) in the absence of an outbreak. Stool or rectal swab cultures for GNRs were obtained from all infants on admission, weekly, and on discharge. GNRs were tested for gentamicin susceptibility and were typed by contour-clamped homogeneous electric field electrophoresis. Transmission of identical strains of GNRs among infants was noted. Shared strains were more gentamicin resistant compared with unique strains (53% vs. 10%; P=.0001). Infants first colonized when they were >1 week of age had more total days of antibiotic treatment and had a higher rate of acquiring a shared and gentamicin-resistant strain, compared with infants colonized earlier. Antibiotic use increases colonization of infants in the NICU with resistant and shared strains of GNRs.

A decade of prevalence surveys in a tertiary-care center: trends in nosocomial infection rates, device utilization, and patient acuity.

OBJECTIVE: To evaluate the usefulness of repeated prevalence surveys to determine trends in the rates of nosocomial infections and to detect changes in risk factors (e.g., use of invasive devices) associated with nosocomial infections. PATIENTS AND METHODS: Ten annual prevalence surveys were conducted by trained infection control practitioners between 1985 and 1995 for acute-care patients on the medical, surgical, pediatric, and obstetric-gynecologic services at a 900-bed, tertiary-care, teaching hospital with 750 acute-care beds. The same methods of chart review and concurrent reporting from nursing, the microbiology and clinical laboratory, and the pharmacy were used each year to collect data on the prevalence of nosocomial infections, invasive-device utilization, and abnormal laboratory indicators. Although data were collected on a single day, a period-prevalence study approach was used, because charts were reviewed for any infection data occurring within the 7 days prior to the survey. RESULTS: The hospital census for acute care patients, as measured by the prevalence surveys, declined sharply over the 10 years, from 673 to 575 patients (P = .02). However, the medical service census increased from 150 to 188 patients (P = .01). During the same period, there was a significant decrease in the mean length of stay, from 7.3 to 6.0 days (P = .01), and a concomitant increase in the mean diagnosis related-group case-mix index, from 1.03 to 1.24 (P = .001). Overall, nosocomial infection rates remained unchanged over the study period (mean of 9.85 infections per 100 patients), but rates of nosocomial bloodstream infection increased from 0.0% in 1985 to 2.3% in 1995 (P = .05). Nosocomial infection rates were significantly higher on the medical and surgical services than on other services (P<.001). Utilization rates increased significantly for Foley catheters (9.0% to 16.0%, P = .002) and ventilators (5.0% to 8.0%, P = .05). CONCLUSIONS: Despite apparent increases in the severity of illness of our patients, overall rates of nosocomial infection remained stable during a decade of study. Rates of nosocomial bloodstream infection increased, in parallel with National Nosocomial Infection Surveillance System data. We found repeated prevalence surveys to be useful in following trends and rates of infection, device utilization, and abnormal laboratory values among patients at our institution. Such methodologies can be valuable and low-cost components of a comprehensive infection surveillance, prevention, and control program and other potential quality-improvement initiatives, because they enable better annual planning of departmental strategies to meet hospital needs.

Management of a Sabiá virus-infected patients in a US hospital.

OBJECTIVE: To describe the hospital precautions used to isolate a Sabiá virus (arenavirus: Arenaviridae)-infected patient in a US hospital and to protect hospital staff and visitors. DESIGN: Investigation of a single case of arenavirus laboratory-acquired infection and associated case-contacts. SETTING: A 900-bed, tertiary-care, university-affiliated medical center. PATIENTS OR OTHER PARTICIPANTS: The case-patient became ill with Sabiá virus infection. The case-contacts consisted of healthcare workers, coworkers, friends, and relatives of the case-patient. INTERVENTION: Enhanced isolation precautions for treatment of a viral hemorrhagic fever (VHF) patient were implemented in the clinical laboratory and patient-care setting to prevent nosocomial transmission. The enhanced precautions included preventing aerosol spread of the virus from the patient or his clinical specimens. All case-contacts were tested for Sabiá virus antibodies and monitored for signs and symptoms of early disease. RESULTS: No cases of secondary infection occurred among 142 case-contacts. CONCLUSIONS: With the frequency of worldwide travel, patients with VHF can be admitted to a local hospital at any time in the United States. The use of enhanced isolation precautions for VHF appeared to be effective in preventing secondary cases by limiting the number of contacts and promoting proper handling of laboratory specimens. Patients with VHF can be managed safely in a local hospital setting, provided that appropriate precautions are planned and implemented.

Molecular analysis of glycopeptide-resistant Enterococcus faecium isolates collected from Michigan hospitals over a 6-year period.

The purpose of this study was to evaluate the molecular relatedness of clinical isolates of glycopeptide-resistant Enterococcus faecium isolates collected from hospitals in Michigan. A total of 379 isolates used in this study were all vancomycin-resistant E. faecium isolates collected from 28 hospitals and three extended-care facilities over a 6-year period from 1991 to 1996. For the 379 isolates, there were 73 pulsed-field gel electrophoresis (PFGE) strain types. Within strain types, there were as many as six restriction fragment differences. Most isolates (70%) belonged to six strain types, which were designated M1 (36%), M2 (3%), M3 (18%), M4 (6%), M10 (4%), and M11 (3%). PFGE strain M1 was cultured from 135 patients in 13 hospitals during the period 1993 to 1996. Strain type M2 was cultured from 11 patients in two hospitals during the period 1991 to 1992 and was not observed after 1992. Strain type M3 was cultured from 70 patients in 10 hospitals during the period of 1994 to 1996. Both M4 and M10 were cultured from 23 patients in three hospitals and from 15 patients in two hospitals, respectively, during 1995 to 1996. M11 was cultured from 13 patients in four hospitals during 1996. A total of 23 of 28 hospitals had evidence of clonal dissemination of some isolates. Plasmid content and hybridization analysis done on 103 isolates from one hospital and two affiliated extended-care facilities indicated that the strains contained from one to eight plasmids. Mating experiments indicated transfer of vancomycin resistance from 94 of these isolates into plasmid-free E. faecium GE-1 at transfer frequencies of <10(-9) to 10(-4). Gentamicin resistance and erythromycin resistance were cotransferred at various frequencies. A probe for the vanA gene hybridized to the plasmids of 23 isolates and to the chromosomes of 72 isolates. A probe for the vanB gene hybridized to the chromosomes of 8 isolates. The results of this study suggest inter- and intrahospital dissemination of vancomycin-resistant E. faecium strains over a 6-year period in southeastern Michigan. The majority of isolates studied belonged to the same few PFGE strains, indicating that clonal dissemination was responsible for most of the spread of resistance that occurred.

Comparison of in vitro activity of trovafloxacin against gram-positive and gram-negative organisms with quinolones and beta-lactam antimicrobial agents.

The in vitro activity of trovafloxacin against 721 Gram-negative and 498 Gram-positive organisms was determined by the standard microdilution broth method using commercially prepared frozen microtiter plates. The activity of trovafloxacin was compared to ofloxacin, ciprofloxacin, amoxicillin/clavulanate, ampicillin/sulbactam (1:1), piperacillin/tazobactam, ceftriaxone, and imipenem. Trovafloxacin had equal or greater activity compared with the other agents tested against Citrobacter diversus, Enterobacter aerogenes, Enterobacter cloacae, Escherichia coli, Haemophilus influenzae, Stenotrophomonas maltophilia, Serratia marcescens, staphylococci, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus viridans, group G streptococci, Enterococcus faecalis, and E. faecium. The reliability of the commercially prepared plates for testing the in vitro activity of the quinolones was evaluated by comparing identical isolates also tested by broth microdilution using laboratory prepared plates. The commercially prepared plates generally correlated, within one- to twofold dilutions, with the laboratory prepared plates. There was, however, a large discrepancy obtained when testing Enterobacter agglomerans and E. cloacae, where the commercially prepared plates yielded a significantly higher MIC90 value.

Nosocomial Candida glabrata colonization: an epidemiologic study.

Candida glabrata has emerged as an important nosocomial pathogen, yet little is known about its epidemiology. We prospectively followed 98 patients admitted to a medical intensive care unit and the bone marrow transplant unit of a university hospital. Samples from environmental surfaces and the hands of hospital personnel were also cultured. Patients with newly acquired C. glabrata strains were compared to controls who were culture negative for C. glabrata. C. glabrata was recovered from multiple sites from 24 patients and three environmental surfaces. Sixteen patients (17%) acquired C. glabrata after admission to the study units. Significant risk factors for the nosocomial acquisition of C. glabrata were prolonged duration of hospitalization in the unit and prior antimicrobial use. Strain delineation by restriction enzyme analysis revealed 28 different strains of C. glabrata; three strain types were common to nine patients. The environmental isolates were of the same strain type and common to five patients (four patients with newly acquired strains). These results suggest the possibility of exogenous nosocomial acquisition of C. glabrata, including the possible acquisition from the hospital environment. Transmission may be by indirect contact since identical strains of C. glabrata were recovered from patients who were geographically and temporally associated.

Renal and perirenal abscesses.

Our knowledge of the spectrum of renal abscesses has evolved as a result of more sensitive radiologic techniques. The classification of intrarenal abscesses currently includes acute focal bacterial nephritis, acute multifocal bacterial nephritis, renal cortical abscess, renal corticomedullary abscess, and xanthogranulomatous pyelonephritis. The clinical presentation of these entities does not differentiate them, however, and various radiographic studies are helpful in making the diagnosis. The intrarenal abscess is usually treated successfully with antibiotic therapy alone. Antistaphylococcal therapy is indicated for the renal cortical abscess, whereas therapy directed against the common gram-negative uropathogens is indicated for most of the other entities. The perinephric abscess is often an elusive diagnosis, has a more serious prognosis, and is more difficult to treat. Drainage of the abscess and sometimes partial or complete nephrectomy, in addition to antibiotic therapy, are required for resolution.

In-vitro activity of trovafloxacin against sensitive and resistant aerobic bacteria using the standard microdilution broth method and Etest.

A comparison of MICs of trovafloxacin (CP-99,219) determined by the standard microdilution broth method versus the Etest was performed for multiple strains of Gram-positive and Gram-negative bacteria. A comparison was also made of the in-vitro activity of trovafloxacin versus ciprofloxacin and ofloxacin. The MIC50 and MIC90 were determined by both methods for each species tested. The Etest resulted in MICs one to two dilutions higher than the microdilution broth method. Trovafloxacin was the most active agent against Gram-positive organisms. Ciprofloxacin was the most active agent against Citrobacter freundii, Proteus mirabilis, Proteus vulgaris, Morganella morganii and Serratia marcescens, while trovafloxacin had equal or greater activity compared with ciprofloxacin and ofloxacin against the other Gram-negative organisms tested. Overall, ofloxacin was the least active agent tested. In addition, the in-vitro activity of trovafloxacin or ciprofloxacin in combination with ampicillin/sulbactam, gentamicin or vancomycin was evaluated. The combination of trovafloxacin and gentamicin was synergic against two of 20 Enterococcus faecium isolates, the combination of trovafloxacin and ampicillin/sulbactam was synergic against two of 24 Enterococcus faecalis isolates, and the combination of ciprofloxacin and gentamicin was synergic against one of 25 Stenotrophomonas maltophilia isolates. All other antibiotic combinations resulted in an additive or indifferent effect.

Control of endemic glycopeptide-resistant enterococci.

OBJECTIVE: To evaluate the epidemiology of, and control measures for, vancomycin-resistant Enterococcus (VRE) in a renal unit. DESIGN: A 3-month, prospective, prevalence culture survey of patients on a 24-bed renal unit. SETTING: A 975-bed community teaching hospital. PATIENTS: Patients admitted to the renal unit over a 3-month period. Patients identified with VRE were each matched with four patients without VRE isolated over the study period. INTERVENTIONS/CONTROL MEASURES: Resistant-organism barrier precautions. To eradicate carriage of VRE, two patients with VRE stool colonization were treated with 5 days of oral doxycycline (100 mg twice per day) and rifampin (300 mg/day). RESULTS: Seven patients with VRE (8 isolates) were identified. Five isolates were Enterococcus faecium (vancomycin MIC = 16 to 256 micrograms/mL), two were Enterococcus faecalis (MICs = 16 and 124 micrograms/mL), and one was Enterococcus gallinarum (MIC = 8.0 micrograms/mL). Eradication of carriage with VRE was accomplished in two patients treated with doxycycline and rifampin. In the final 30 days of the culture survey and at 9 months, there were no further patients with VRE identified. CONCLUSIONS: Resistant-organism precautions and elimination of patient carriage may be useful measures for controlling the spread of low-prevalence endemic vancomycin-resistant Enterococcus.

Educational needs and opportunities for the hospital epidemiologist.

The role of the hospital epidemiologist has changed substantially over the last 30 years as medical care has become more complex. The hospital epidemiologist needs training in methods for surveillance, prevention, and control of nosocomial infections. The hospital epidemiologist also must know how to apply these methods to other areas, including the epidemiology of noninfectious adverse outcomes of medical care. Training in hospital epidemiology should be a defined part of every infectious disease fellowship training program. Ancillary and additional training is available from several sources.

Comparison of rectal and perirectal swabs for detection of colonization with vancomycin-resistant enterococci.

Patients whose gastrointestinal tracts are colonized with vancomycin-resistant enterococci (VRE) may serve as a reservoir for nosocomial transmission. We compared the sensitivities and concordance of several methods used to detect VRE colonization. Eighty-two paired rectal and perirectal swabs were obtained from 13 patients over a 9-day period. The sensitivity of both rectal and perirectal swabs was 79%. There was 100% concordance of culture results between simultaneously obtained rectal and perirectal swabs, and the quantities of growth were similar by these two methods of detection. Our data suggest that rectal and perirectal swabs are equally sensitive for the detection of VRE colonization.

Invasive Candida guilliermondii infection: in vitro susceptibility studies and molecular analysis.

Candida guilliermondii is rarely isolated from humans. We describe a case of disseminated C. guilliermondii with associated purulent pericarditis, despite high-dose amphotericin B (AmB), in a 19-year-old female with aplastic anemia who underwent BMT. In vitro susceptibility studies of the 13 clinical isolates, two control strains and one environmental isolate revealed a minimum inhibitory concentration (MIC) range of (0.19-1.56 micrograms/ml) for AmB and (1.25-10 micrograms/ml) for fluconazole. Pulsed-field gradient gel electrophoresis was performed to evaluate possible similarities between strains. This case is significant for several reasons, the high degree and prolonged duration of fungemia despite high-dose AmB and concomitant flucytosine, the change in in vitro susceptibility during therapy, the initial misidentification of the yeast isolate, and the invasiveness of the organism. The poor response to therapy may have been due to the severe and sustained neutropenia and the high MICs of C. guilliermondii to AmB.

Extraosseous epidural tuberculoma: case report and review.

Extraosseous epidural tuberculoma has been reported infrequently, in spite of the widespread availability in recent years of computerized axial tomography and magnetic resonance imaging that can detect bony involvement not apparent on roentgenography with plain films. Thirty-two cases of extraosseous epidural tuberculoma have been reported in the English-language literature; however, only seven of these were radiologically and microbiologically confirmed. The single case from North America was reported over 30 years ago. We describe a patient with a spinal epidural mass due to Mycobacterium tuberculosis that was not associated with bony involvement and review the epidemiology, pathophysiology, presentation, and outcome of the previously reported cases.