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L Barth Reller

Publications and source records attributed to L Barth Reller.

At least 37 records · Page 2Linked to original sources
PubMed2005

Staphylococcus aureus bacteremia in patients with prosthetic devices: costs and outcomes.

PURPOSE: Although Staphylococcus aureus is a leading cause of nosocomial infection, little is known about the impact of S. aureus bacteremia on patients with prosthetic devices. This investigation sought to define the clinical outcome, health care resource use, and infection-associated costs of S. aureus bacteremia in patients with prostheses. SUBJECTS AND METHODS: All hospitalized patients with a prosthetic device and S. aureus bacteremia during the 96-month study period were identified prospectively. Clinical data were collected at the time of hospitalization. Data regarding infection-related resource utilization and infection-related costs within 12 weeks of the initial bacteremia were also recorded. RESULTS: 298 patients with > or =1 prosthesis and S. aureus bacteremia were identified (cardiovascular device--122 patients, orthopedic device--73 patients, long-term catheter--71 patients, and other devices-32 patients). Overall, 58% of patients underwent surgery as a consequence of the infection. Infection-related complications occurred in 41% and the overall 12-week mortality was 27%. The mean infection-related cost was 67439 dollars for patients with hospital-acquired S. aureus bacteremia and 37868 dollars for community-acquired S. aureus bacteremia (cost difference 29571 dollars; 95% confidence interval, 14370 dollars-49826 dollars). Rates of device infection, complications, 12-week mortality, and mean cost varied by prosthesis type. CONCLUSION: S. aureus bacteremia in patients with prosthetic devices is associated with frequent complications, substantial cost, and significant health care resource utilization.

Adult↗
PubMed2005

Clinical profile and strain relatedness of recurrent enterococcal bacteremia.

We defined the molecular epidemiology of recurrent enterococcal bacteremia using pulsed field gel electrophoresis. We identified 27 patients, comprising 60 episodes; strain relatedness was demonstrated in 8 patients with isolates separated by up to 6 y. Carriage of pathogenic enterococci may be prolonged, although re-infection with novel strains is more commonly seen.

Adolescent↗
PubMed2005

Costs and outcomes among hemodialysis-dependent patients with methicillin-resistant or methicillin-susceptible Staphylococcus aureus bacteremia.

OBJECTIVE: 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. DESIGN, SETTING, AND PATIENTS: 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. RESULTS: 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 dollars vs 13,978 dollars; P = .012) and after 12 weeks (25,518 dollars vs 17,354 dollars; 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. CONCLUSIONS: 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.

APACHE↗
PubMed2005

Clinical outcomes and costs due to Staphylococcus aureus bacteremia among patients receiving long-term hemodialysis.

OBJECTIVE: To examine the clinical outcomes and costs associated with Staphylococcus aureus bacteremia among hemodialysis-dependent patients. DESIGN: Prospectively identified cohort study. SETTING: A tertiary-care university medical center in North Carolina. PATIENTS: Two hundred ten hemodialysis-dependent adults with end-stage renal disease hospitalized with S. aureus bacteremia. RESULTS: The majority of the patients (117; 55.7%) underwent dialysis via tunneled catheters, and 29.5% (62) underwent dialysis via synthetic arteriovenous fistulas. Vascular access was the suspected source of bacteremia in 185 patients (88.1%). Complications occurred in 31.0% (65), and the overall 12-week mortality rate was 19.0% (40). The mean cost of treating S. aureus bacteremia, including readmissions and outpatient costs, was $24,034 per episode. The mean initial hospitalization cost was significantly greater for patients with complicated versus uncomplicated S. aureus bacteremia ($32,462 vs $17,011; P = .002). CONCLUSION: Interventions to decrease the rate of S. aureus bacteremia are needed in this high-risk, hemodialysis-dependent population.

Academic Medical Centers↗
PubMed2005

Controlled clinical comparison of plastic versus glass bottles of BacT/ALERT PF medium for culturing blood from children.

The plastic pediatric BacT/ALERT (bioMérieux, Durham, N.C.) PF (PPF) is a new nonvented aerobic culture medium in a clear plastic bottle designed to prevent breakage. We compared the performance of the new PPF bottle to that of the present glass BacT/ALERT PF bottle for the recovery of microorganisms as well as for the time to detection of growth in samples of blood obtained for culture from children. We found that the PPF and PF bottles were comparable for recovery of microorganisms and that the safety advantage of plastic bottles can be achieved without compromising performance.

Bacteremia↗
PubMed2005

Validation of performance of plastic versus glass bottles for culturing anaerobes from blood in BacT/ALERT SN medium.

To validate performance, we compared the new plastic BacT/ALERT (bioMérieux, Durham, NC) SN bottle to the current glass SN bottle with samples of blood obtained for culture from adults and found them comparable for both recovery and speed of detection of microorganisms. We conclude that the safety advantage of plastic bottles can be achieved without compromising performance.

Adult↗
PubMed2005

Controlled clinical comparison of plastic and glass bottles of BacT/ALERT FA medium for culturing organisms from blood of adult patients.

A new, clear-plastic nonvented aerobic FA bottle, designed to prevent breakage, has been developed for the BacT/ALERT blood culture system. We assessed the new plastic FA bottle by comparing its performance with that of the current glass FA bottle for recovery of microorganisms and time to detection of growth in blood samples obtained for culture from adult patients with suspected bloodstream infections. We conclude that the BacT/ALERT plastic and glass FA bottles are comparable for recovery of microorganisms and that the safety advantage of plastic bottles can be achieved without compromising performance.

Adult↗
PubMed2005

Streptococcus pneumoniae antigen test using positive blood culture bottles as an alternative method to diagnose pneumococcal bacteremia.

Recovery of Streptococcus pneumoniae from positive blood culture bottles may be difficult due to autolysis of pneumococci. Therefore, we evaluated the performance of the Binax NOW S. pneumoniae antigen test with samples from positive blood culture bottles and defined the duration of detectable pneumococcal antigen in these bottles. Use of the S. pneumoniae antigen test is an alternative method for identifying S. pneumoniae from positive blood culture bottles and may enable a diagnosis of pneumococcal bacteremia despite negative subcultures.

Antigens, Bacterial↗
PubMed2005

Selection of strains for quality assessment of the disk induction method for detection of inducible clindamycin resistance in Staphylococci: a CLSI collaborative study.

A nine-laboratory collaborative study was conducted to select positive and negative quality assessment control strains for the detection of inducible clindamycin resistance in staphylococci. Four strains of Staphylococcus aureus were tested as unknowns on 10 different days in each laboratory using the recently recommended CLSI (formerly NCCLS) disk diffusion method and the inoculum purity control method. Strains contained either macrolide-lincosamide-streptogramin B (MLSB) resistance genes encoded by erm(A) or erm(C) or a macrolide resistance efflux pump encoded by msr(A). Based upon the results of this study, strain UT 32 (now designated ATCC strain BAA-977) containing erm(A) is recommended as the positive control organism for inducible clindamycin resistance. Strain UT 25 (now designated ATCC BAA-976), which harbors the efflux pump encoded by msr(A), is recommended as the negative control organism.

Anti-Bacterial Agents↗
PubMed2005

Broad-range (pan) Salmonella and Salmonella serotype typhi-specific real-time PCR assays: potential tools for the clinical microbiologist.

We describe broad-range salmonellae (ie, Salmonella) and Salmonella serotype Typhi-specific LightCycler (Roche Diagnostics, Indianapolis, IN) real-time polymerase chain reaction assays. We validated these with a battery of 280 bacteria, 108 of which were salmonellae representing 20 serotypes. In addition, 298 isolates from 170 clinical specimens that were suspected to possibly represent Salmonella were tested with the pan- Salmonella assay. Finally, the pan-Salmonella assay also was used to test DNA extracts from 101 archived, frozen stool specimens, 55 of which were culture-positive for salmonellae. Both assays were 100% sensitive and specific when cultured isolates of the battery were tested. The pan- Salmonella assay also characterized correctly all salmonellae on the primary isolation agar and was 96% sensitive (53/55) and 96% specific (49/51) when nucleic acid extracts from direct stool specimens were tested. These assays represent potential tools the clinical microbiologist could use to screen suspect isolates or stool specimens for Salmonella.

DNA, Bacterial↗
PubMed2004

Persistent bacteremia due to methicillin-resistant Staphylococcus aureus infection is associated with agr dysfunction and low-level in vitro resistance to thrombin-induced platelet microbicidal protein.

BACKGROUND: The causes of persistent bacteremia (PB) due to methicillin-resistant Staphylococcus aureus (MRSA) are poorly understood. This investigation examined potential associations between PB with key clinical features and several in vitro bacterial genotypic and phenotypic characteristics, in isolates from 1 institution. METHODS: Pulsed-field gel electrophoresis (PFGE) relatedness, thrombin-induced platelet microbicidal protein (tPMP)-susceptibility phenotype, accessory gene regulator (agr) genotype and functionality (via delta-lysin production), and autolysis phenotypes were assessed in MRSA isolates from the bloodstream of 21 prospectively identified patients with PB (blood cultures positive after > or =7 days of therapy) and of 18 patients with resolving bacteremia (RB) (sterile blood cultures within the first 2-4 days of therapy) due to MRSA. RESULTS: The 2 groups had comparable baseline characteristics but differed in their clinical courses (e.g., endocarditis was more frequent in patients with PB than in those with RB [43% vs. 0%, respectively; P=.0016]); isolates from patients with PB exhibited higher rates of (1) survival in vitro after exposure to tPMP (22.4+/-14.8% vs. 11.6+/-6.5%, respectively; P=.005); (2) defective delta-lysin production (71.4% vs. 38.9%, respectively; P=.057); (3) non-agr genotype II profile (100% vs. 77.8%, respectively; P=.037); and (4) overrepresentation of a specific PFGE genotype (85.7% vs. 44.4%, respectively; P=.015). CONCLUSIONS: Isolates from patients with PB differed from those in patients with RB, in several in vitro characteristics. Further studies will be necessary to define how these factors might affect clinical outcome.

Anti-Bacterial Agents↗
PubMed2004

Virulence associated with outbreak-related strains of Burkholderia cepacia complex among a cohort of patients with bacteremia.

The Burkholderia cepacia complex includes 9 genomovars. The relative virulence of each is unknown. Host and pathogen features associated with mortality were evaluated among patients with B. cepacia complex bacteremia. Cases were ascertained through review of blood culture results for the period of May 1996 through May 2002. Isolates were identified to species level with 16S rDNA and recA-based species-specific polymerase chain reaction analyses and recA restriction fragment-length polymorphism. Strain typing was performed with pulsed-field gel electrophoresis. Fifty-three patients with B. cepacia complex bacteremia were identified; only 9 (17%) had cystic fibrosis. Twenty-five patients (47%) died within 14 days of bacteremia. After controlling for comorbid conditions and therapeutic interventions, 2 outbreak-related strains of Burkholderia cenocepacia (genomovar III) were associated with 14-day mortality (odds ratio, 5.5; 95% confidence interval, 1.20-25.02). B. cenocepacia is an emerging nosocomial pathogen. Certain strains are associated with an enhanced capacity for interpatient spread and poor outcome.

Adolescent↗
PubMed2004

Clinical predictors of bloodstream infections and mortality in hospitalized Malawian children.

BACKGROUND: In sub-Saharan Africa, bloodstream infections (BSI) are a major cause of pediatric mortality. Because of limited resources and facilities in these developing countries, treatment often must be based solely on clinical observations and patient history and includes the use of broad spectrum antimicrobials, a factor in the emergence of antibiotic resistance. METHODS: During July 28 through August 18, 1998 we analyzed clinical, epidemiologic and microbiologic data from a cohort of 225 hospitalized children in Malawi, Africa, to determine clinical indices associated with the presence/absence of BSI and/or mortality for use in settings with minimal microbiologic laboratory and intensive care facilities. RESULTS: BSI (n = 35 children) were associated with malnutrition, chronic cough, lethargy by history, lethargy on examination and oral thrush; 92% of children without these symptoms were BSI-negative. Mortality (21 of 173 children with known mortality status) was associated with malnutrition, lethargy on examination, prior receipt of antimalarials and acute decreased feeding. Of those with > or =2 of these indices 69% died; of those with <2 of the indices 94% survived. Infection with human immunodeficiency virus was not significantly related to either BSI or mortality status. CONCLUSIONS: Malnutrition, but not HIV, was strongly related to both BSI and mortality. Assessment of these BSI and mortality indices at hospital admission provides rapid, cost-free indication of which children are most/least in need of empiric antimicrobial therapy or intensive observation, thereby maximizing appropriate use of antimicrobials and limited facilities while minimizing inappropriate antimicrobial usage.

Acute Disease↗
PubMed2004

Development, implementation, and impact of acceptability criteria for serologic tests for infectious diseases.

Serologic testing is essential for the diagnosis of some infectious diseases and yet is fraught with potential pitfalls. All parts of the diagnostic process must be optimized to ensure that serologic tests perform adequately. Recognizing that a lack of clinical data and correctly timed, paired sera frequently led to uninterpretable serology results at our laboratory, we developed and implemented simple acceptability criteria for serologic tests. We assessed the impact of these criteria by comparing submissions and results for the year before and the year after implementation of the criteria. The number of serologic tests performed declined by 25% after implementation of the acceptability criteria, despite an increase in requests for serologic tests. Inappropriate testing of acute-phase sera alone fell from 49 to 0% (P < 0.001) for the tests monitored. Appropriate submission of paired sera rose from 9 to 19% (P = 0.006). The proportion of results classified as interpretable rose from 52 to 100% (P < 0.001). We recommend that acceptability criteria be developed and applied to samples submitted to clinical microbiology laboratories for serologic testing.

Bacterial Infections↗
PubMed2004

Molecular epidemiologic evaluation of endocarditis due to Oerskovia turbata and CDC group A-3 associated with contaminated homograft valves.

Oerskovia turbata is an unusual bacterial cause of endocarditis and septicemia in immunocompromised patients. In this study, we compared 12 isolates from a 1975 medical center cluster, 11 originally identified as O. turbata (four from the blood of a homograft aortic valve-associated endocarditis patient and seven from contaminated homograft valves) and one CDC group A-3 strain from the blood of a second endocarditis patient with fatal outcome, with eight control strains from unrelated locations. The control strains included type and reference strains of O. turbata, Cellulomonas hominis, and CDC group A-3. The four blood isolates from the first patient and six of the valve isolates shared identical biochemical, antimicrobial susceptibility, and BglI ribotype patterns that differed from the second patient's isolate and control strains. The blood isolate from the second patient and the remaining valve isolate shared a phenotypic and genotypic profile and were phenotypically identical to, but epidemiologically different from, the CDC group A-3 reference strain with the strain-specific enzyme. Also, these isolates differed from the type strain and the other reference strains of C. hominis and O. turbata. Our results indicate that the four blood isolates from the first patient and six of the homograft valve isolates represent a single clone of O. turbata associated with endocarditis. Additionally, our results indicate that the blood isolate from the second patient and one of the homograft valve isolates differ from O. turbata and C. hominis and represent a unique clone of CDC group A-3 associated with fatal endocarditis.

Actinomycetales↗
PubMed2004

Multicenter evaluation of use of penicillin and ampicillin as surrogates for in vitro testing of susceptibility of enterococci to imipenem.

Imipenem is approved by the U.S. Food and Drug Administration (FDA) for treatment of infections caused by Enterococcus faecalis. However, there are no NCCLS guidelines for testing susceptibility of enterococci against imipenem. To assess whether or not ampicillin or penicillin could be used as a surrogate for broth microdilution (BMD) testing of imipenem versus Enterococcus species, 633 strains of E. faecalis, E. faecium, and other enterococci isolated from blood cultures of patients at three geographically distinct university hospitals were tested by the NCCLS BMD and disk diffusion (DD) methods. Using FDA susceptibility breakpoints for imipenem and NCCLS breakpoints for penicillin and ampicillin, categorical agreement (CA) for penicillin-imipenem and ampicillin-imipenem tested with E. faecalis and E. faecium by BMD was >/=94% but was </=90% for other enterococci. Using the DD method, CA for ampicillin-imipenem tested with E. faecalis and E. faecium was >/=98% and was 92% for other enterococci; CA for penicillin-imipenem was 91% for E. faecalis, 98% for E. faecium, and 87% for other enterococci. Further analysis showed that testing E. faecalis with ampicillin resulted in no false-susceptible (FS) or false-resistant (FR) results by BMD, no FS results by DD, and a single FR result by DD (0.2%), whereas testing with penicillin resulted in no FS results by BMD or DD and two FR results by BMD (0.4%). For E. faecium and other enterococci, the combination of FS and FR results was such that surrogate testing with penicillin or ampicillin appears not to be sufficiently reliable to be used clinically. We conclude that ampicillin is an accurate predictor of the in vitro activity of imipenem against E. faecalis.

Ampicillin↗
PubMed2004

Antifungal susceptibilities of Cryptococcus neoformans.

Susceptibility profiles of medically important fungi in less-developed countries remain uncharacterized. We measured the MICs of amphotericin B, 5-flucytosine, fluconazole, itraconazole, and ketoconazole for Cryptococcus neoformans clinical isolates from Thailand, Malawi, and the United States and found no evidence of resistance or MIC profile differences among the countries.

Antifungal Agents↗