Biomedical subjects

R Arbeit

Publications and source records attributed to R Arbeit.

6 recordsLinked to original sources

PubMed1997

Multicenter typing comparison of sporadic and outbreak Clostridium difficile isolates from geographically diverse hospitals.

In a collaborative study by three laboratories, arbitrarily primed polymerase chain reaction (AP-PCR), HindIII restriction enzyme analysis (REA), and pulsed-field gel electrophoresis (PFGE) using SmaI were compared for typing of Clostridium difficile. The study included 30 isolates from nosocomial outbreaks in six geographically disparate hospitals and 15 isolates from sporadic cases of C. difficile diarrhea. REA distinguished a total of 23 types representing 10 groups; AP-PCR performed at Deaconess Hospital resolved 19 types; AP-PCR performed at the Centers for Disease Control resolved 15 types. Thirty isolates exhibited degradation of larger sized fragments during processing and therefore were nontypeable by PFGE; among the remaining 15 isolates, PFGE resolved 11 types. Outbreak isolates in five different hospitals represented REA group J and constituted a single AP-PCR strain. In summary, nosocomial outbreaks of C. difficile diarrhea in five hospitals were associated with a single genetic lineage as resolved by multiple strain typing systems.

Bacterial Typing Techniques↗

PubMed1994

Comparison of traditional and molecular methods of typing isolates of Staphylococcus aureus.

Fifty-nine Staphylococcus aureus isolates and 1 isolate of Staphylococcus intermedius were typed by investigators at eight institutions by using either antibiograms, bacteriophage typing, biotyping, immunoblotting, insertion sequence typing with IS257/431, multilocus enzyme electrophoresis, restriction analysis of plasmid DNA, pulsed-field or field inversion gel electrophoresis, restriction analysis of PCR-amplified coagulase gene sequences, restriction fragment length polymorphism typing by using four staphylococcal genes as probes, or ribotyping. Isolates from four well-characterized outbreaks (n = 29) and a collection of organisms from two nursing homes were mixed with epidemiologically unrelated stock strains from the Centers for Disease Control and Prevention. Several isolates were included multiple times either within or between the sets of isolates to analyze the reproducibilities of the typing systems. Overall, the DNA-based techniques and immunoblotting were most effective in grouping outbreak-related strains, recognizing 27 to 29 of the 29 outbreak-related strains; however, they also tended to include 3 to 8 epidemiologically unrelated isolates in the same strain type. Restriction fragment length polymorphism methods with mec gene-associated loci were less useful than other techniques for typing oxacillin-susceptible isolates. Phage typing, plasmid DNA restriction analysis, and antibiogram analysis, the techniques most readily available to clinical laboratories, identified 23 to 26 of 29 outbreak-related isolates and assigned 0 to 6 unrelated isolates to outbreak strain types. No single technique was clearly superior to the others; however, biotyping, because it produced so many subtypes, did not effectively group outbreak-related strains of S. aureus.

Bacterial Typing Techniques↗

PubMed1993

Trimethoprim-sulfamethoxazole prophylaxis in granulocytopenic patients with acute leukemia: evaluation of serum antibiotic levels in a randomized, double-blind, placebo-controlled Department of Veterans Affairs Cooperative Study.

Despite widespread use of trimethoprim-sulfamethoxazole (TMP-SMZ) for prophylaxis in neutropenic patients, questions remain regarding its efficacy, toxicity, the risk of selection of resistant isolates, and the relation of its activity to selective decolonization vs. the attainment of direct inhibitory levels within blood and tissues. We evaluated the effect of TMP-SMZ (160/800 mg orally every 12 hours) in 42 adult granulocytopenic patients (< 100 absolute neutrophils/mm3, mean duration 13.3 days) undergoing chemotherapy for acute leukemia at 11 participating Veterans Administration Medical Centers in a randomized, double-blind, placebo-controlled trial. No significant differences in survival, frequency of bacteremia, overall infections, use of systemic antimicrobial therapy, or adverse effects, including myelosuppression, were observed between patients receiving TMP-SMZ vs. those receiving placebo. All patients acquired trimethoprim-resistant organisms. Concentrations of trimethoprim in serum were significantly lower before febrile episodes than when patients were afebrile. These results suggest that the purported activity of TMP-SMZ may be related to the serum concentration achieved. Moreover, the results highlight the need for additional study of the value of antibiotic prophylaxis in neutropenic patients.

Acute Disease↗

PubMed1985

Method for the serological typing of the capsular polysaccharides of Staphylococcus aureus.

A method is described for typing Staphylococcus aureus capsular polysaccharides that is based on direct bacterial cell agglutination and immunoprecipitation of cell extracts with monospecific antisera. Encapsulated strains were identified by their inagglutinability with teichoic acid antisera. The typing sera reacted specifically with extracts of eight prototype strains.

Agglutination Tests↗

PubMed1984

Nosocomial endocarditis.

We analyzed 14 cases of nosocomial infective endocarditis which occurred over a seven-year period at the Beth Israel Hospital in Boston, and compared them with 90 cases of community-acquired endocarditis. Patients with nosocomial endocarditis were older, more often female, and had a greater incidence of underlying valvular heart disease and bacteremia precipitating invasive procedures (93% v 50%, p less than .05). Forty-three percent of patients had infection at the site of prosthetic valves or intracardiac prosthetic material. The disease carried a significantly higher mortality than community-acquired endocarditis (43% v 11%, p less than .01). The clinical presentation was acute and the infecting organisms reflected the site of origin of bacteremia, with staphylococci from skin and enterococci from urinary sources. Half of the cases in this series may have been prevented by the application of currently recommended preventive and therapeutic practices. Nosocomial endocarditis occurs in a definable sub-population of hospitalized patients and is potentially preventable.

Catheters, Indwelling↗

PubMed1980

Invasive pulmonary aspergillosis in an apparently nonimmunocompromised host.

Invasive aspergillosis generally occurs in patients with hematologic malignancies, neutropenia or other severe derangements of host defense. An adult patient without such a predisposition, and without a previous history of susceptibility to infections, had rapidly progressive respiratory failure associated with repeated growth of Aspergillus fumigatus on culture of sputum and bronchoscopy specimens. At autopsy he proved to have invasive pulmonary aspergillosis.

Aspergillosis↗