Harold W. Horowitz

Outbreak of vancomycin-, ampicillin-, and aminoglycoside-resistant Enterococcus faecium bacteremia in an adult oncology unit.

An outbreak of bacteremia caused by Enterococcus faecium with high-level resistance to vancomycin (MIC of > or = 256 micrograms/ml), ampicillin (MIC of > or = 64 micrograms/ml), and gentamicin or streptomycin (MIC of > or = 2,000 micrograms/ml) occurred in an adult oncology unit from June 1991 to May 1992. Active surveillance for the presence of this organism in stool or perianal cultures was begun in September 1991. Between June 1991 and May 1992, seven patients with bacteremia and 22 noninfected carriers of the organism in stool were identified. The vanA gene, tested for by PCR and gene probe, was present in all isolates evaluated. All bacteremic patients also had resistant E. faecium present in a stool or perianal culture; the stool isolates tested were closely related to the respective blood isolates as determined by pulsed-field gel electrophoresis. Antibiotic regimens using high-dose ampicillin and an aminoglycoside were ineffective with four patients. Five patients (71%) had multiple positive blood cultures; four of these patients died. Following a multiple logistic regression analysis, it was found that bacteremic patients received a significantly greater number of total antibiotic days compared with noninfected stool carriers (P = 0.019). The emergence of E. faecium with high-level resistance to vancomycin, ampicillin, and aminoglycosides underscores the importance of performing susceptibility testing on all clinically significant isolates. In the neutropenic adult oncology patient, bacteremia with this organism is of probable gastrointestinal origin, is often persistent, and is refractory to treatment with ampicillin in combination with an aminoglycoside. Prolonged use of antibiotics may predispose patients with gastrointestinal colonization to develop bacteremia. Images

Infection-control measures reduce transmission of vancomycin-resistant enterococci in an endemic setting.

Shortly after the emergence of vancomycin resistance in enterococci, vancomycin-resistant enterococci (VRE) spread throughout the United States (1). In some hospitals, VRE became established as endemic nosocomial pathogens (2). The Centers for Disease Control and Prevention issued comprehensive recommendations for preventing VRE transmission (3). These recommendations, in combination with a program for reducing antimicrobial use, are referred to as enhanced infection-control strategies. They were instituted in an adult oncology unit in which VRE were endemic (4). We report the results of a prospective study that compared the effectiveness of enhanced infection-control strategies with the effectiveness of standard VRE infection-control practices. Methods Our study was conducted at an 11-room, 22-bed adult oncology unit in a 650-bed tertiary care hospital. Standard infection-control practices and enhanced infection-control strategies are given in Table 1. Standard practices were in effect from November 1993 until July 1994, and enhanced strategies were in effect from July 1994 until July 1995. Perianal surveillance cultures were obtained by using previously reported methods (4). Our study was approved by the institutional review boards of New York Medical College, Westchester Medical Center, and the Centers for Disease Control and Prevention. Table 1. Standard Infection-Control Practices Compared with Enhanced Infection-Control Strategies for Patients in an Adult Oncology Unit Data Collection Patients at risk for VRE were patients with VRE-negative perianal cultures. New VRE-positive patients were patients who had a first VRE-positive culture while they were hospitalized in the oncology unit. Bloodstream infection with VRE was defined by using standard criteria (5). Demographic characteristics and clinical patient data were collected prospectively from patient charts. Antimicrobial use was abstracted from computerized pharmacy records. Observational monitoring of health care worker compliance with handwashing and gown and glove use was conducted regularly. Microbiological Methods Perianal swabs and environmental cultures were inoculated into M-enterococcus broth (Difco Laboratories, Detroit, Michigan) or Enterococcosel broth (Becton Dickinson Microbiology Systems, Sparks, Maryland), both of which were supplemented with 6 g of vancomycin. Vancomycin-resistant enterococci were identified from broths (6), isolates were characterized to the species level (7), minimum inhibitory concentrations for vancomycin were determined (8), and selected isolates were compared for relatedness by pulsed-field gel electrophoresis (9, 10); all of these procedures were done by using previously reported methods. Statistical Analysis Patient characteristics were compared by using the chi-square test for categorical data and the Student t-test or Wilcoxon rank-sum test for continuous variables. Person-time rate comparisons were performed by using Pepi 2.0 software (Stone Mountain, Georgia). All P values are two-tailed. Results Incidence of Vancomycin-Resistant Enterococci We obtained cultures for VRE from all 259 patients (100%) in 404 admissions to the unit during use of enhanced infection-control strategies and 167 of 184 patients (91%) in 210 admissions to the unit during use of standard infection-control practices. The number of patients at risk for acquiring VRE was 212 of 259 patients (82%) during use of enhanced infection-control strategies and 160 of 167 patients (96%) during use of standard infection-control practices. Patients hospitalized during the use of enhanced infection-control strategies were older than patients hospitalized during the period when standard infection-control practices were used (mean age SD, 57.3 15.4 years compared with 53.4 18 years; P=0.03). The two groups also differed with respect to oncologic diagnosis (P=0.06). During use of enhanced infection-control strategies, more patients had gastrointestinal cancer (57 of 212 patients [26.9%] compared with 20 of 160 patients [12.5%]) and fewer patients had hematologic cancer (60 patients [28.3%] compared with 69 patients [43.1%]). However, the two groups were similar with respect to the percentages of patients with lung cancer (29 patients [13.7%] compared with 26 patients [16.3%]); breast, uterine, or prostate cancer (36 patients [17%] compared with 23 patients [14.4%]); and other diagnoses (aplastic anemia, melanoma, bladder cancer, renal cancer, or head and neck cancer) (30 patients [14.2%] compared with 22 patients [13.7%]). The two groups were also similar with respect to sex (118 men [55.7%] compared with 85 men [53.1%]; P>0.2), patients requiring transfer to the intensive care unit during admission (18 patients [8.5%] compared with 8 patients [5.0%]; P>0.2), and number of admissions in which patients received chemotherapy (242 admissions [59.9%] compared with 135 admissions [64.3%]; P>0.2). During use of enhanced infection-control strategies, significant reductions were seen in the rate of VRE bloodstream infection (0.45 patients per 1000 patient-days compared with 2.1 patients per 1000 patient-days; relative rate ratio, 0.22 [95% CI, 0.05 to 0.92]; P=0.04) and the VRE colonization rate (10.3 patients per 1000 patient-days compared with 20.7 patients per 1000 patient-days; relative rate ratio, 0.5 [CI, 0.33 to 0.75]; P<0.001] (Table 2). Among patients with an oncologic diagnosis of hematologic cancer, the VRE bloodstream infection rate (1.4 patients per 1000 patient-days compared with 3.2 patients per 1000 patient-days; relative rate ratio, 0.45 [CI, 0.10 to 1.96]; P>0.2) and the VRE colonization rate (15.7 patients per 1000 patient-days compared with 24.4 patients per 1000 patient-days; relative rate ratio, 0.65 [CI, 0.37 to 1.13]; P=0.13) were lower during use of enhanced infection-control strategies, but the differences were not statistically significant. Among patients with solid tumors, the VRE colonization rate was also lower during use of enhanced infection-control strategies (8.6 patients per 1000 patient-days compared with 13.2 patients per 1000 patient-days; relative rate ratio, 0.65 [CI, 0.34 to 1.24]; P=0.2); no patient had VRE bloodstream infection. Table 2. Outcomes of Enhanced Infection-Control Strategies Compared with Outcomes of Standard Infection-Control Practices in an Adult Oncology Unit Thirty-two of the 41 perianal isolates obtained during use of enhanced infection-control strategies were Enterococcus faecium, 5 isolates were E. faecalis, 3 isolates were E. avium, and 1 isolate was E. gallinarum. The minimum inhibitory concentration of vancomycin for the 41 VRE isolates was at least 64 g/mL (range, 64 to>1024 g/mL). Pulsed-field gel electrophoresis showed 23 distinct E. faecium isolates. Environmental Surveillance After discharge of VRE-positive patients and disinfection of the patients rooms, the number of environmental surfaces with VRE was significantly lower than that detected while VRE-positive patients were still occupying their rooms (13 of 162 cultures [8%] compared with 45 of 167 cultures [26.9%]; P<0.001). By using pulsed-field gel electrophoresis, we found that for all seven of the patient-environment pairs tested, vancomycin-resistant E. faecium isolates recovered from environmental surfaces were identical to the isolate recovered from the patient occupying the room. Compliance with Enhanced Infection-Control Strategies Most persons (111 of 121 [91.7%]) who entered the rooms of VRE-positive patients used gowns and gloves appropriately. Gowns and gloves were located immediately outside 48 of 66 rooms (72.7%). All persons using gowns and gloves washed their hands after glove removal. Changes in Antimicrobial Use Compared with use during the standard infection-control period, use of vancomycin, imipenem-cilastatin, ceftazidime, ciprofloxacin, aztreonam, and gentamicin during the enhanced infection-control period was significantly reduced (Table 2). Use of amikacin also decreased, although the difference was not statistically significant. Use of clindamycin increased significantly (Table 2). Discussion Infection-control experts anticipated that it would be difficult to interrupt transmission of VRE after the microorganism became established as an endemic nosocomial pathogen (3). Studies conducted in centers with endemic VRE found that contact isolation measures with surveillance cultures (11) and contact isolation measures with surveillance cultures and controlled vancomycin use (2) did not reduce VRE transmission. Several factors may have contributed to the success of the enhanced infection-control strategies. Our study was conducted in a single unit, which allowed ongoing surveillance of a sample of patients that was infrequently transferred between hospital units. The enhanced infection-control strategies focused on comprehensive reduction of person-to-person VRE transmission by adding the following: assigning patients to geographic cohorts, assigning nurses to patient cohorts, providing extensive education to patients and staff members, using gowns and gloves on room entry, monitoring compliance, and obtaining environmental surveillance cultures to our standard infection-control practices of performing contact isolation and obtaining surveillance cultures. Although the presence of 23 distinct vancomycin-resistant E. faecium isolates in the unit made it difficult to demonstrate person-to-person transmission, the reduction in VRE colonization rates associated with enhanced infection-control strategies suggests that VRE was being spread by person-to-person contact. Reduction in use of several classes of antimicrobial agents in addition to vancomycin was probably an important component in preventing VRE acquisition during use of enhanced infection-control strategies. Use of cephalosporin (12) and metronidazole (13) are risk factors for VRE colonization or infection, and reduction of cephalosporin use has been associated

Simultaneous Human Granulocytic Ehrlichiosis and Lyme Borreliosis

Infection with the agent of human granulocytic ehrlichiosis occurs in areas in which Borrelia burgdorferi and Babesia microti are endemic.1–4 The most likely vector of human granulocytic ehrlichiosis is the deer tick, Ixodes scapularis, which is also the vector of Lyme disease and babesiosis.3,4 Coinfection in humans with both the agent of human granulocytic ehrlichiosis and B. burgdorferi can be anticipated because ixodes ticks infected with the two organisms have been identified in several locales.3–5 The diagnosis of simultaneous infection with B. burgdorferi and the agent of human granulocytic ehrlichiosis is important because the natural history of .xa0.xa0.

Perinatal Transmission of the Agent of Human Granulocytic Ehrlichiosis

Human granulocytic ehrlichiosis was first described in the United States, in the northern Midwest, in 1994.1 Human granulocytic ehrlichiosis is caused by an organism, still referred to as the agent of human granulocytic ehrlichiosis, that is similar to two animal pathogens, Ehrlichia phagocytophila and E. equi. 2–4 Transmission of human granulocytic ehrlichiosis occurs through the bites of ixodes ticks, which are the arthropod vectors for Borrelia burgdorferi and Babesia microti. 5,6 Human granulocytic ehrlichiosis is an acute, febrile, nonspecific illness that may be severe enough to cause hospitalization and even death, particularly in the elderly.1,7,8 We describe a .xa0.xa0.

Costs and savings associated with infection control measures that reduced transmission of vancomycin-resistant enterococci in an endemic setting

OBJECTIVEnTo determine the costs and savings of a 15-component infection control program that reduced transmission of vancomycin-resistant enterococci (VRE) in an endemic setting.nnnDESIGNnEvaluation of costs and savings, using historical control data.nnnSETTINGnAdult oncology unit of a 650-bed hospital.nnnPARTICIPANTSnPatients with leukemia, lymphoma, and solid tumors, excluding bone marrow transplant recipients.nnnMETHODSnCosts and savings with estimated ranges were calculated. Excess length of stay (LOS) associated with VRE bloodstream infection (BSI) was determined by matching VRE BSI patients with VRE-negative patients by oncology diagnosis. Differences in LOS between the matched groups were evaluated using a mixed-effect analysis of variance linear-regression model.nnnRESULTSnThe cost of enhanced infection control strategies for 1 year was

Cerebral Syphilitic Gumma Confirmed by the Polymerase Chain Reaction in a Man with Human Immunodeficiency Virus Infection

116,515. VRE BSI was associated with an increased LOS of 13.7 days. The savings associated with fewer VRE BSI (

NOCARDIOSIS IN PATIENTS WITH HUMAN IMMUNODEFICIENCY VIRUS INFECTION : REPORT OF 2 CASES AND REVIEW OF THE LITERATURE

123,081), fewer patients with VRE colonization (

Analysis of Sequences and Loci of p44 Homologs Expressed by Anaplasma phagocytophila in Acutely Infected Patients

2,755), and reductions in antimicrobial use (

Antimicrobial susceptibility of Ehrlichia phagocytophila.

179,997) totaled

Clinical and Laboratory Spectrum of Culture-Proven Human Granulocytic Ehrlichiosis: Comparison with Culture-Negative Cases

305,833. Estimated ranges of costs and savings for enhanced infection control strategies were