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J A Kraft

Publications and source records attributed to J A Kraft.

9 recordsLinked to original sources
PubMed1996

Multicenter evaluation of four methods for Clostridium difficile detection: ImmunoCard C. difficile, cytotoxin assay, culture, and latex agglutination.

A three-center study was undertaken to compare several test methods for the detection of Clostridium difficile, associated toxin, or related markers by using 927 stool specimens. Methods included direct assay of cytotoxin in stool by tissue culture, C. difficile bacterial culture followed by cytotoxin assay, bacterial culture alone, latex agglutination assay, and the ImmunoCard C. difficile test (Meridian Diagnostics, Inc.). The sensitivities, as determined against direct cytotoxin assay results, of the ImmunoCard C. difficile and latex agglutination assays were 84 and 67%, respectively (92 and 77%, respectively, when adjusted for bacterial culture outcomes). Evaluation for C. difficile-associated disease (CDAD) among 864 patients was based on clinical criteria for antibiotic-associated diarrhea combined with laboratory evidence of toxin or toxin-producing C. difficile in stool specimens. The sensitivity of each test method for screening of CDAD was as follows: bacterial culture, 95%; culture with cytotoxin assay of isolates, 90%; ImmunoCard C. difficile test, 83%; cytotoxin assay 82%; and latex agglutination assay, 67% (P < or = 0.05 versus all other methods). The standard deviations of the test sensitivity statistics between study sites were ranked as follows: cytotoxin assay (+/- 3.1%) < ImmunoCard C. difficile test (+/- 5.7%) < latex agglutination assay (+/- 12.3%) < culture (+/- 24.7%) < culture with cytotoxin assay (+/- 28.0%). The data support the use of the ImmunoCard C. difficile test as an adjunct for the diagnosis of CDAD.

Bacterial Toxins↗
PubMed1996

Performance of Meridian ImmunoCard Mycoplasma test in a multicenter clinical trial.

Serology is the principal laboratory method used to diagnose Mycoplasma pneumoniae infection. Meridian Diagnostics has developed the ImmunoCard Mycoplasma kit, a 10-min card-based enzyme-linked immunosorbent assay (ELISA) designed to detect immunoglobulin M (IgM) antibodies to M. pneumoniae. We compared the ImmunoCard with two M. pneumoniae IgM-specific assays (immunofluorescence assay [IFA] and ELISA) and a standard complement fixation (CF) procedure using 896 specimens submitted to clinical laboratories for M. pneumoniae serology. Equivocal results obtained by CF, IFA, or ELISA were resolved by testing with an additional method or by reviewing patient chart information. The ImmunoCard had sensitivities ranging from 74% compared with the ELISA to 96% compared with CF results with IFA. ImmunoCard specificities ranged from 85% compared with the IgM-specific ELISA to 98% compared with IgM-specific IFA results resolved with clinical chart review. We also compared the ImmunoCard results with consensus results of 694 specimens tested on at least two non-ImmunoCard methods because of the lack of a "gold standard" for M. pneumoniae serology. Overall, the ImmunoCard Mycoplasma IgM assay had 90% sensitivity, 93% specificity, and 92% agreement with the consensus results. The ImmunoCard is technically less complex and requires less equipment that the three other assays. Our results indicate that the ImmunoCard Mycoplasma IgM assay is a valid and simple procedure which can reduce technologist time (and, thus, labor cost) and turnaround time for laboratories analyzing small numbers of specimens (< 10 per batch) submitted for IgM anti-M. pneumoniae testing.

Adult↗
PubMed1993

The use of a commercially available enzyme immunoassay for the detection of Clostridium difficile toxin A.

A commercially available enzyme immunoassay (EIA) for the detection of Clostridium difficile toxin A (Premier Toxin A EIA, Meridian Diagnostics, Cincinnati, Ohio) was compared with tissue culture cytotoxicity assay, enterotoxigenic culture, and latex agglutination test for the laboratory diagnosis of C difficile-associated disease. When evaluated for detection of C difficile-associated disease using clinical specimens, EIA was the most sensitive (83.1%) and tissue culture cytotoxicity assay was the most specific test with EIA, tissue culture cytotoxicity assay and enterotoxigenic culture having similar correlation values (96.6, 96.1, 94.0%, respectively). The latex agglutination test was not as accurate (89.7% correlation) as the other three tests due mainly to its poor sensitivity (47.9%). The EIA is a rapid, easy-to-use alternative to tissue culture cytotoxicity assay for detection of C difficile-associated disease.

Bacterial Toxins↗
PubMed1991

Development of a rapid enzyme immunoassay for Clostridium difficile toxin A and its use in the diagnosis of C. difficile-associated disease.

A rapid (2.5 h) direct enzyme immunoassay (EIA) for Clostridium difficile toxin A was developed for clinical use. Specimen centrifugation and filtration were not required. The EIA detected toxin A levels in patient stool as low as 20 pg (2 ng/ml of stool). The test was 5,000 times more sensitive for toxin A than it was for toxin B and did not react with a panel of other bacterial species with the exception of one highly toxigenic strain of Clostridium sordellii. The EIA was compared with the cytotoxin assay, culture of toxigenic C. difficile (toxigenic culture), and latex agglutination by using 313 fresh stool specimens submitted from patients with suspected C. difficile-associated disease. Results read visually and with a plate reader were similar. Sixty-two specimens were positive by one or more tests, but only 22 (35%) were positive by all four laboratory methods. The EIA was 84.1% sensitive and 98.9% specific when it was compared with the cytotoxin assay. The use of toxigenic culture to referee discrepant results (EIA versus cytotoxin assay) showed the EIA sensitivity and specificity to be 95.1 and 99.3%, respectively, with respect to other laboratory methods. Patient charts were reviewed for antibiotic-associated diarrhea on 108 specimens, including all those that were positive by at least one test method. Of 34 patients determined to have C. difficile-associated disease, 29 (85.3%) were positive by EIA, 32 (94.1%) were positive by the cytotoxin assay, 27 (79.4%) were positive by toxigenic culture, and 20 (58.8%) were positive by latex agglutination. Seven patients with antibiotic-associated diarrhea had a positive latex result, but results were negative by EIA, the cytotoxin assay, and toxigenic culture. The EIA demonstrated high specificity and good sensitivity for C. difficile-associated disease cases. The test can be used alone or in combination with the cytotoxin assay or toxigenic culture to provide rapid and sensitive results.

Antibody Specificity↗
PubMed1986

Detection of Pseudomonas mesophilica as a source of nosocomial infections in a bone marrow transplant unit.

Pseudomonas mesophilica was isolated from fungal blood cultures of two bone marrow transplant recipients who consecutively occupied the same room. The isolation of P. mesophilica was temporally associated with febrile illness in these two granulocytopenic patients at 1 and 3 weeks posttransplant. A third patient, housed separately on the same bone marrow transplant unit, had nasopharyngeal colonization by this organism. Epidemiologic risk factors in common included staff, medications, and oral and perineal irrigations with tap water. Surveillance cultures detected P. mesophilica in none of 24 pharmaceutical preparations and in 10 of 40 tap water samples (100 to 600 CFU/ml) from implicated and control rooms on the same floor. Antimicrobial susceptibility testing of 14 patients and environmental isolates by agar dilution revealed similar profiles; some environmental isolates exhibited higher MICs. Because of restrictive nutritional and temperature requirements, P. mesophilica is undetected by many clinical laboratory protocols and may represent a previously undetected source of febrile illness in neutropenic patients.

Adolescent↗