Center for Disease Control Diagnostic Immunology Proficiency Testing Program results for 1978

Self Cite

Whole-cell sonicates of Treponema pallidum, Nichols strain, were evaluated in an enzyme-linked immunosorbent assay (ELISA) for syphilis, and results were read in a Dynatek Microelisa Reader. The antigen was evaluated with sera from patients with syphilis, persons presumed normal, and biological false-positives. Two hundred and ninety-seven sera were tested by the ELISA with T. pallidum antigens, the Venereal Disease Research Laboratory (VDRL) slide test, the fluorescent treponemal antibody absorption (FTA-Abs) test, and the microhemagglutination assay for T. pallidum antibodies (MHA-TP). The results of all of the tests were compared. The ELISA, with 89.3% sensitivity, was less sensitive than the VDRL (93.3%) and FTA-Abs (100.0%) tests but more sensitive than the MHA-TP (76.0%). The ELISA was considerably more sensitive in primary syphilis than ttie MHA-TP. Specificity was as follows: ELISA, 98.5%; FTA-Abs test, 97.8%; MHA-TP, 98.2%; and VDRL test, 92.7%. The ELISA has good potential as a confirmatory test in the serodiagnosis of syphilis.

Section: Discussionmentioning

confidence: 99%

Evaluation of the microenzyme-linked immunosorbent assay with Treponema pallidum antigen

Pope¹,

Hunter²,

Feeley³

1982

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“…Satisfactory performance requires careful absorption of nonspecific inhibitors, and the method is not easily automated. Reports from the Centers for Disease Control indicate that there is considerable laboratory to laboratory variation, both in the detection of antibody and in the determination of titer by HAI (13)(14)(15). The enzyme-linked immunosorbent assay (ELISA), which has been shown to offer good sensitivity, ease and speed of performance, and adaptability to semiautomation, has been suggested as an alternative method for rubella serology.…”

mentioning

confidence: 99%

Comparison of hemagglutination inhibition test and enzyme-linked immunosorbent assay for determining antibody to rubella virus

Shekarchi¹,

Sever²,

Tzan³

et al. 1981

The hemagglutination inhibition test (HAI) and the enzyme-linked immunosorbent assay (ELISA) for detecting antibody to rubella virus were compared by testing 25 sets of paired sera taken before and after infection and 10 sets of sera taken during acute and convalescent stages of the disease and by screening 700 serum samples from the Collaborative Perinatal Project, NIH/NINCDS. The tests were found to be comparable in their ability to detect positive and negative sera, rises in titers, and seroconversions. When a purified antigen and carefully prepared reagents were used, ELISA was found to be as accurate and reliable as HAI. ELISA required no pretreatment of serum, could easily be automated, and was less time-consuming than HAI.

“…Antistreptolysin O test results indicated that some of the variation in results was because many of the participants were reconstituting the streptolysin reagent with water at room temperature. 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 î" This produced significantly elevated titers compared with results obtained when cold water was used (26). Departure from the recommended method of mixing slide tests for multiple streptococcal antibodies was shown to be a factor in some erroneous results.…”

Section: Resultsmentioning

confidence: 99%

“…Details of specimen preparation and tabulations of results for each survey are included in quarterly summary analyses (10)(11)(12)(13)(18)(19)(20)(21)(22) annual critiques (14,23,24), and professional journal publications (3,16,17,(25)(26)(27). Briefly, specimens were adjusted to the desired reactivity, filtered through sterile membrane filters, and dispensed into suitable vials or tubes.…”

Section: Methodsmentioning

confidence: 99%

Assessment of laboratory improvement by the Center for Disease Control Diagnostic Immunology Proficiency Testing Program

Taylor¹,

Fulford²

1981

Self Cite

The data accumulated from 1969 to 1979 in the Diagnostic Immunology portion of the Center for Disease Control Proficiency Testing Program were evaluated for evidence of change in performance among the participating laboratories. Evidence of improved performance was found for the rubella, rheumatoid factor, tularemia, quantitative immunoglobulin (immunoglobulin G, A, and M), and hepatitis B tests. No evidence of change was detected for the streptococcal enzyme, C-reactive protein, infectious mononucleosis, antinuclear antibodies, Salmonella and Brucella agglutinins, and syphilis tests. Data obtained from other tests were inadequate to determine trends. In most tests, deficiencies were identified which could be corrected and thereby could improve performance. It is pointed out that proficiency testing not only improves laboratory performance, but also can be used to evaluate performance levels, identify method, standard, or performance deficiencies, educate, estimate impact of possible changes, serve as external quality control, and document changes.