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J R Edwards

Publications and source records attributed to J R Edwards.

At least 55 records · Page 3Linked to original sources
PubMed1997

Evidence of interhospital transmission of extended-spectrum beta-lactam-resistant Klebsiella pneumoniae in the United States, 1986 to 1993. The National Nosocomial Infections Surveillance System.

BACKGROUND: In addition to single-hospital outbreaks, interhospital transmission of extended-spectrum beta-lactam-resistant (ESBLR) Klebsiella pneumoniae has been suspected in some reports. However, these studies lacked sufficient epidemiological information to confirm such an occurrence. METHODS: We reviewed the surveillance data reported to the National Nosocomial Infections Surveillance (NNIS) System during 1986 to 1993 for K pneumoniae isolates and their susceptibility to either ceftazidime, cefotaxime, ceftriaxone, or aztreonam. Pulsed-field gel electrophoresis (PFGE) was used to study available ESBLR K pneumoniae isolates. RESULTS: Among 8,319 K pneumoniae isolates associated with nosocomial infections, 727 (8.7%) were resistant or had intermediate-level resistance to at least one of these antibiotics. One hospital (hospital A) accounted for 321 isolates (44.2%) of ESBLR K pneumoniae. During 1986 to 1993, the percentage of K pneumoniae isolates that were ESBLR increased from 0 to 57.7% in hospital A, from 0 to 35.6% in NNIS hospitals 0 to 20 miles from hospital A (area B), and from 1.6 to 7.3% in NNIS hospitals more than 20 miles from hospital A, including hospitals located throughout the United States. Analysis of PFGE restriction profiles showed a genetic relationship between a cluster of isolates from hospital A and some isolates from one hospital in area B, and consecutive admission in these two hospitals was confirmed for two patients from whom isolates were available. CONCLUSIONS: These data provide evidence of interhospital transmission of ESBLR K pneumoniae in one region of the United States and stress the interrelationship between hospitals when trying to control antimicrobial resistance.

Anti-Bacterial Agents↗
PubMed1996

Nosocomial infections among neonates in high-risk nurseries in the United States. National Nosocomial Infections Surveillance System.

BACKGROUND: Nosocomial infections result in considerable morbidity and mortality among neonates in high-risk nurseries (HRNs). PURPOSE: To examine the epidemiology of nosocomial infections among neonates in level III HRNs. METHODS: Data were collected from 99 hospitals with HRNs participating in the National Nosocomial Infections Surveillance system, which uses standard surveillance protocols and nosocomial infection site definitions. The data included information on maternal acquisition of and risk factors for infection, such as device exposure, birth weight category (< or = 1000, 1001 through 1500, 1501 through 2500, and > 2500 g), mortality, and the relationship of the nosocomial infection to death. RESULTS: From October 1986 through September 1994, these hospitals submitted data on 13 179 nosocomial infections. The bloodstream was the most frequent site of nosocomial infection in all birth weight groups. Nosocomial pneumonia was the second most common infection site, followed by the gastrointestinal and eye, ear, nose, and throat sites. The most common nosocomial pathogens among all neonates were coagulase-negative staphylococci, Staphylococcus aureus, enterococci, Enterobacter sp, and Escherichia coli. Group B streptococci were associated with 46% of bloodstream infections that were maternally acquired; coagulase-negative staphylococci were associated with 58% of bloodstream infections that were not maternally acquired, most of which (88%) were associated with umbilical or central intravenous catheters. CONCLUSIONS: Bloodstream infections, the most frequent nosocomial infections in all birth weight groups, should be a major focus of surveillance and prevention efforts in HRNs. For bloodstream infections, stratification of surveillance data by maternal acquisition will help focus prevention efforts for group B streptococci outside the HRN. Within the nursery, bloodstream infection surveillance should focus on umbilical or central intravenous catheter use, a major risk factor for infection.

Bacterial Infections↗
PubMed1995

Evolution of hospital participation in the National Nosocomial Infections Surveillance System, 1986 to 1993.

OBJECTIVE: To study changes in the use of National Nosocomial Infections Surveillance System (NNIS) surveillance components since 1986 that could reflect an evolution in the way in which NNIS hospitals conduct surveillance of nosocomial infections. METHOD: We analyzed NNIS data from 1986 to 1993 collected at the 199 US hospitals that participated in the NNIS system during this period. RESULTS: The number of hospitals participating in the NNIS system increased threefold between 1986 and 1993. A parallel increase was noticed in the amount of surveillance data for all NNIS components except for the hospital-wide component. The percentage of all hospitals reporting at least 1 calendar month per year of data from the hospital-wide component decreased from 95% in 1986 to 37% in 1993. During this period, use of the hospital-wide component was greater among the hospitals whose first participation in the NNIS system occurred before 1987. CONCLUSION: Interest by NNIS hospitals in the hospital-wide component apparently decreased between 1987 and 1993. In contrast, the interest in NNIS components that allow calculation of risk-adjusted nosocomial infection rates (intensive care unit, high-risk nursery, and surgical patient components) increased dramatically after 1986. This increased interest in surveillance with NNIS components that allow risk adjustment and interhospital comparison of infection rates suggests that the feasibility of collection of and interest in such data are high.

Cross Infection↗
PubMed1995

Ciprofloxacin resistance among nosocomial Pseudomonas aeruginosa and Staphylococcus aureus in the United States.

OBJECTIVE: We attempted to determine if an increase in resistance to ciprofloxacin occurred among nosocomial pathogens, especially Pseudomonas aeruginosa and Staphylococcus aureus. METHODS: We examined 1989-1992 ciprofloxacin susceptibility results from 8,517 P aeruginosa and 9,021 S aureus isolates associated with nosocomial infections reported to the National Nosocomial Infections Surveillance System. RESULTS: For S aureus, 27.1% of isolates were resistant to ciprofloxacin; of methicillin-resistant S aureus isolates, 80% also were resistant to ciprofloxacin. A logistic regression model found that ciprofloxacin resistance was more common among S aureus isolated from the urinary and respiratory tracts than from other sites of isolation, and among isolates that were methicillin resistant. After controlling for these factors, the model showed a 123% increase in the odds of ciprofloxacin resistance from 1989-1990 to 1991-1992. For P aeruginosa, 4.7% of the isolates were resistant to ciprofloxacin. Resistance varied by site of infection and rose most dramatically for respiratory tract isolates from 2.0% in 1989-1990 to 5.3% in 1991-1992. CONCLUSION: Resistance to ciprofloxacin is more frequent among nosocomial S aureus than among P aeruginosa and is increasing rapidly among S aureus isolates and from selected sites among P aeruginosa isolates.

Ciprofloxacin↗
PubMed1995

Meropenem: a microbiological overview.

Meropenem is a parenteral carbapenem antibiotic which has excellent bactericidal activity in vitro against almost all clinically significant aerobes and anaerobes. Its high activity is explained by ease of entry into bacteria combined with good affinity for essential penicillin binding proteins, including those associated with cell lysis. Breadth of spectrum is due, in part, to stability to all serine-based beta-lactamases, including those which hydrolyse third-generation cephalosporins. Meropenem has an antibacterial spectrum which is broadly similar to that of imipenem but, whilst slightly less active against staphylococci and enterococci, it is more active against Pseudomonas aeruginosa, all Enterobacteriaceae and Haemophilus influenzae. Amongst common human pathogens, only methicillin-resistant staphylococci and Enterococcus faecium are uniformly resistant to meropenem. The meropenem MICs for penicillin-resistant Streptococcus pneumoniae are higher than for penicillin-susceptible strains but the organisms remain susceptible. Clinical susceptibility in vitro to meropenem is defined by MICs of < or = 4 mg/L, intermediate susceptibility by MICs of 8 mg/L and MICs of > or = 16 mg/L define resistance; equivalent figures for zones of growth inhibition are > or = 14 (susceptible), 12-13 (intermediate) and < or = 11 (resistant) mm. Studies in guinea pig models of systemic infection and infections localised to the lungs, urinary tract and the central nervous system, some of which used immunocompromised animals, confirm the potential of meropenem demonstrated in vitro. These factors, combined with the human plasma, tissue or urinary concentrations of meropenem which exceed modal MICs for the pathogens isolated in clinical trials for most or all of the recommended 8 h dosing interval, predict that meropenem should be efficacious in the treatment of infections at many body sites.

Animals↗
PubMed1995

Efficacy of meropenem in experimental meningitis.

Meropenem and comparator antibiotics, including ceftriaxone, ceftazidime, benzyl penicillin and a combination of ampicillin plus gentamicin, were evaluated in a model of bacterial meningitis in the guinea-pig. The model is an acute infection in which challenge with each organism, if untreated, causes an increase in numbers of white blood cells, elevation of protein concentrations and 6-8 log10 cfu/mL of bacteria in the CSF. Infections caused by Haemophilus influenzae, Neisseria meningitidis, three strains of Streptococcus pneumoniae (two penicillin-resistant), Escherichia coli, Pseudomonas aeruginosa and Listeria monocytogenes all responded to meropenem, which was as active as the comparator agents in all studies, and was more active in most. Of particular note were the results seen against S. pneumoniae (penicillin-resistant) infections, in which meropenem was significantly more effective than ceftriaxone. Also notable were results from the P. aeruginosa infection where meropenem, at low doses, was more effective than ceftazidime. Activity against L. monocytogenes was equivalent to that produced by treatment with the combination of ampicillin plus gentamicin, even when treatment was delayed. These results show that, in an animal model, meropenem penetrates into CSF in concentrations sufficient to produce significant reductions in the numbers of common and less common pathogens.

Ampicillin↗
PubMed1995

Long-term granulocyte-macrophage colony-stimulating factor and immunosuppression in the treatment of acquired severe aplastic anemia.

PURPOSE: Seven children with newly diagnosed acquired severe aplastic anemia (SAA) were treated with a combination of long-term granulocyte-macrophage colony-stimulating factor (GM-CSF) and immunosuppression to assess the potential for GM-CSF to induce sustained neutrophil recovery, reduce the incidence of infection, and enhance the therapeutic efficacy of immunosuppression. METHODS: Patients received a 14-day course of i.v. antithymocyte globulin 15 mg/kg/day with oral prednisone 1 mg/kg/day, long-term daily oral cyclosporine A 10 mg/kg/day, and long-term daily s.c. GM-CSF 5 micrograms/kg/day. RESULTS: All seven children recovered an absolute neutrophil count of > 1.0 x 10(9)/L within 3.5 months of diagnosis (mean 60 days). Of the six children followed throughout their entire illness (follow-up 10-27 months), five are platelet and red cell transfusion independent (three off-therapy, two on tapering therapy) and one continues on therapy with a diminishing transfusion requirement. Compared with seven children treated previously with immunosuppression alone, children who received GM-CSF spent fewer days in the hospital and were less likely to develop infection. CONCLUSIONS: The addition of GM-CSF to immunosuppressive therapy appears to be beneficial in the treatment of children with acquired SAA with GM-CSF stimulating granulopoiesis. The children are better protected from infectious complications while immunosuppressive agents achieve full therapeutic potential.

Adolescent↗
PubMed1995

Traumatic anterior dislocation of the hip: spectrum of plain film and CT findings.

Traumatic anterior dislocation of the hip represents 11% of all hip dislocations and is classified into superior and inferior types [1]. Whereas inferior anterior hip dislocation is easily recognized on an anteroposterior radiograph of the pelvis, the radiographic appearance of superior anterior hip dislocation is less straightforward, often leading to an initial misdiagnosis of posterior hip dislocation. Misdiagnosis of the direction (anterior versus posterior) of a hip dislocation can result in failed closed reduction or an improper surgical approach to open reduction. In addition, recognition of associated impaction fractures is important, as patients with this finding have a greater tendency to develop traumatic arthritis [2, 3]. This pictorial essay, which is based on our experience with 20 cases of anterior hip dislocation, including five of the rare superior type, illustrates the spectrum of radiographic findings and distinguishing features associated with anterior hip dislocation.

Adult↗
PubMed1995

Graft-versus-host-disease prophylaxis for matched unrelated donor bone marrow transplantation: comparison between cyclosporine-methotrexate and cyclosporine-methotrexate-methylprednisolone.

We performed a sequential study comparing two regimens, cyclosporine-methotrexate (CsA-MTX) and cyclosporine-methotrexate-methylprednisolone (CsA-MTX-MP) for graft-versus-host disease (GVHD) prophylaxis in patients undergoing matched unrelated donor bone marrow transplantation (MUD BMT). Study end-points were the development of GVHD, various infectious complications and survival. Twenty nine patients with malignant hematologic disease without HLA-compatible family donors were treated between May 1990 and November 1993. All donors were volunteers from the National Marrow Donor Program (NMDP) serologically HLA-A-A, B and DR identical. MLC reactivity and high resolution DR DNA typing were not used to exclude donors. Sixteen patients received CsA-MTX and 13 patients received CsA-MTX-MP. CsA and MTX doses were the same in both groups: CsA 1.5 mg/kg i.v. over 2h every 12h beginning the day prior to transplant (day-1) and MTX 10 mg/m2 i.v. bolus on days +1, +3 and +6 with leucovorin on days +2, +4 and +7. MP was administered at a dose of 0.25 mg/kg i.v. every 12h beginning on day +7 and increased to 0.5 mg/kg on day +14. Beginning on day +35 MP and CsA were tapered 5% per week with targeted discontinuation at 6 months. Both groups were comparable for primary disease, preparative regimen, recipient age (median 33 VS 33 years), donor age (median 39 vs 39.5 years), donor-recipient sex, donor ABO mismatch and serologic CMV positivity. All patients received similar supportive care.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Laboratory data which differentiate meropenem and imipenem.

Meropenem and imipenem are carbapenems which are distinguishable from all other currently available beta-lactam antibiotics by breadth of antibacterial spectrum and stability to beta-lactamases, but can be differentiated one from another. Meropenem is relatively stable to human renal dehydropeptidase-I (DHP-I); it does not require to be co-administered with cilastatin and consequently, unlike imipenem, will be administered as a single agent. In vitro both meropenem and imipenem are active against almost all clinically important aerobic and anaerobic bacteria. Differences in potency are seen but few may be of clinical significance: imipenem is more active against enterococci and meropenem is more active against Pseudomonas aeruginosa, Pseudomonas cepacia, Haemophilus influenzae and Proteus, Morganella and Providencia species. The primary target of imipenem is PBP2 in P. aeruginosa whilst meropenem has high affinity for both PBP2 and 3; this may contribute to greater potency against this organism. Laboratory evaluations predict that meropenem will not be seizurogenic, which combined with activity against likely pathogens, identified its potential for the treatment of bacterial meningitis. This has been investigated in a guinea-pig model in which meropenem exhibited potent activity against the common meningeal pathogens and also infections caused by penicillin-resistant Streptococcus pneumoniae or Listeria monocytogenes. Clinical experience will determine the significance of these differences.

Animals↗
PubMed1995

Serosurvey of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus infection among hospital-based surgeons. Serosurvey Study Group.

BACKGROUND: Because occupational blood contact places health-care workers at risk for infection with bloodborne pathogens, we wanted to estimate the prevalence of infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) among hospital-based surgeons and correlate the results with occupational and nonoccupational risk factors. STUDY DESIGN: All surgeons in training or in practice in general surgery, obstetrics and gynecology, or orthopedics at 21 hospitals in moderate to high AIDS incidence areas were eligible to participate in a voluntary, anonymous serosurvey. Serum samples were tested for HIV antibody, for HCV antibody, and for markers of HBV infection: hepatitis B surface antigen, total antibody to hepatitis B core antigen, and antibody to hepatitis B surface antigen. RESULTS: Of 2,887 eligible surgeons, 770 (27 percent) participated in the study. One of 740 surgeons not reporting nonoccupational risk factors was HIV seropositive (0.14 percent, upper limit 95 percent confidence interval [CI] equals 0.64 percent). None of 20 participants reporting nonoccupational HIV risk factors and none of ten not responding to the question on nonoccupational risk factors were HIV positive. Of 129 (17 percent) participants with past or current HBV infection, three (0.4 percent) had chronic HBV infection; all were negative for hepatitis B e antigen. Risk factors for HBV infection included not receiving hepatitis B vaccine (odds ratio [OR] 14.7, 95 percent CI 8.3 to 26.0) and practicing surgery at least ten years (OR 2.2, 95 percent CI 1.3 to 3.8). Seven (0.9 percent) participants had anti-HCV. CONCLUSIONS: Although not necessarily generalizable to all surgeons in moderate to high AIDS incidence areas, these results do not indicate a high rate of previously undetected HIV infection among surgeons who trained or practiced in these areas, or both. Hepatitis B virus posed the highest risk of infection with a bloodborne pathogen, followed by HCV and HIV.

General Surgery↗
PubMed1995

[Preclinical evaluation of meropenem, a new parenteral carbapenem].

Meropenem is a new carbapenem antibiotic that is stable to human renal dehydropeptidase-I (DHP-I) and exhibits potent bactericidal activity against almost all clinically significant aerobic and anaerobic bacteria. Activity is achieved through rapid entry into bacteria, resisting hydrolysis by all serine-based beta-lactamases, both of chromosomal or plasmid origin, and high affinity for vital penicillin binding proteins. The antibacterial spectrum of meropenem has been investigated extensively in a world-wide programme of studies. The results from all of these studies are consistent and identify in vitro differences between meropenem and imipenem. Both agents demonstrate high activity against Gram-positive aerobes with meropenem slightly less active than imipenem but significantly more potent than imipenem against Haemophilus influenza, all Enterobacteriaceae and 2-4 fold more active against Pseudomonas aeruginosa and most other pseudomonas. The spectrum of carbapenems is superior to that of all other beta-lactams. This is achieved, in part, by stability to the chromosomal beta-lactamases which hydrolyse ceftazidime, cefotaxime and ceftriaxone and against which newer agents like cefpirome and cefepime are not fully stable. Meropenem is also stable to the new plasmid-mediated enzymes which are responsible for significant elevation of MIC's of all cephalosporins and penicillins. When tested against P. Aeruginosa which have become resistant to imipenem therapy, these strains remained susceptible to meropenem. The activity of meropenem against anaerobes is at least as potent as metronidazole and clindamycin. These impressive in vitro data have been the basis for an extensive clinical evaluation programme in many indications including infections caused by single or multiple pathogens.

Animals↗
PubMed1994

Soil and agronomic factors associated with cadmium accumulations in kidneys of grazing sheep.

Mean concentration of cadmium (Cd) in kidneys of hogget sheep from 67 flocks grazing in the Agricultural Region of Western Australia was tested for association with soil, pastoral, climatic and nutritional factors. Hoggets grazing pastures on acidic soils and soils with a sandy-textured surface had higher Cd concentrations in kidneys than hoggets grazing pastures on more alkaline soils or soils with a clay-textured surface. Application of more than 100 kg of phosphatic fertiliser during the past 3 years to loamy soils was also associated with greater Cd concentration in kidneys of the grazing animals.

Animal Feed↗
PubMed1993

Job demands and worker health: three-dimensional reexamination of the relationship between person-environment fit and strain.

The most influential study of the person-environment (P-E) fit approach to stress was conducted by J. R. P. French, R. D. Caplan, and R. V. Harrison (1982). Unfortunately, this study operationalized fit using various transformations of difference scores, thereby introducing numerous substantive and methodological problems. In the present study, the authors reanalyze data from French et al., using a procedure described by J. R. Edwards (in press) that avoids problems with difference scores and captures the underlying three-dimensional relationship between E, P, and strain. Results resolve ambiguities in the French et al. findings and identify relationships between E, P, and strain that, although consistent with P-E fit theory, cannot be adequately represented by fit measures such as those used by French et al. Implications for P-E fit research are discussed.

Adaptation, Psychological↗
PubMed1993

Nosocomial infections in surgical patients in the United States, January 1986-June 1992. National Nosocomial Infections Surveillance (NNIS) System.

OBJECTIVES: To describe the distribution of nosocomial infections among surgical patients by site of infection for different types of operations, and to show how the risk of certain adverse outcomes associated with nosocomial infection varied by site, type of operation, and exposure to specific medical devices. DESIGN: Surveillance of surgical patients during January 1986-June 1992 using standard definitions and protocols for both comprehensive (all sites, all operations) and targeted (all sites, selected operations) infection detection. SETTING AND PATIENTS: Acute care US hospitals participating in the National Nosocomial Infection Surveillance (NNIS) System: 42,509 patients with 52,388 infections from 95 hospitals using comprehensive surveillance protocols and an additional 5,659 patients with 6,963 infections from 11 more hospitals using a targeted protocol. RESULTS: Surgical site infection was the most common nosocomial infection site (37%) when data were reported by hospitals using the comprehensive protocols. When infections reported from both types of protocols were stratified by type of operation, other sites were most frequent following certain operations (e.g., urinary tract infection after joint prosthesis surgery [52%]). Among the infected surgical patients who died, the probability that an infection was related to the patient's death varied significantly with the site of infection, from 22% for urinary tract infection to 89% for organ/space surgical site infection, but was independent of the type of operation performed. The probability of developing a secondary bloodstream infection also varied significantly with the primary site of infection, from 3.1% for incisional surgical site infection to 9.5% for organ/space surgical site infection (p < .001). For all infections except pneumonia, the risk of developing a secondary bloodstream infection also varied significantly with the type of operation performed (p < .001) and was generally highest for cardiac surgery and lowest for abdominal hysterectomy. Surgical patients who developed ventilator-associated pneumonia were more than twice as likely to develop a secondary bloodstream infection as nonventilated pneumonia patients (8.1% versus 3.3%, p < .001). CONCLUSIONS: For surgical patients with nosocomial infection, the distribution of nosocomial infections by site varies by type of operation, the frequency with which nosocomial infections contribute to patient mortality varies by site of infection but not by type of operation, and the risk of developing a secondary bloodstream infection varies by type of primary infection and, except for pneumonia, by type of operation.

Cause of Death↗