Evaluation of automated large-scale screening tests for syphilis.

Abstract

Previous authors (Pugh and Gaze, 1966;Wagstaff et al, 1969) have reported favourably on the use of the Technicon AutoAnalyzer for automation of the CWR and RPCFT, but one of the main problems seemed to be the continuous flow system's limited rate of testing. If all specimens were tested against cardiolipin and Reiter antigens separately, and all those giving positive or doubtful results were retested against complement alone, it would be difficult to test more than 150 samples each day as allowance must be made for the time required to prepare the machine for use, to wash it through after testing is finished, and to transcribe the results. This would not be considered a significant improvement on the manual test. It is, of course, possible to

Screening tests for syphilis. A comparison of the Treponema pallidum haemagglutination assay with two automated serological tests.

“…In the comparisons summarised in Tables 2 and 3, the TPHA was slightly more sensitive than the ARPCFT, and the most sensitive combination of tests was the ART and TPHA, although the difference was marginal in the case of the Fuzizoki TPHA. Somewhat surprisingly, the most specific test in all three comparisons was the ART, with a total of 69 positives and no false negatives, thus confirming our earlier observations on this test (Macfarlane et al, 1976). The false positive rate for the Wellcome TPHA 1:40 was 13 5% (five out of 37), and for the Fuzizoki TPHA 10 8 % (four out of 37), but the Wellcome TPHA 1:40 recorded a lower false negative rate of 0-16% compared with 0-32% for the Fuzizoki TPHA.…”

“…The method used for the automated tests described by Macfarlane et al (1976) was slightly modified. The complement titration was performed using a weak positive serum and the end point was selected to give a predetermined reading with this serum.…”

Is repeated retreatment necessary for HIV‑negative serofast early syphilis patients?

“…It is difficult for clinicians to assess the biological significance of the serofast state (15). Although nontreponemal tests, such as the toluidine red unheated serum test, the rapid plasma reagin serological test and the venereal disease research laboratory slide test, are able to measure IgG and IgM antibodies to TP and potentially to cardiolipin and lipoidal material released from damaged host cells during syphilis infection, other illnesses that produce tissue damage may also lead to positive results (16). In clinical practice, it is a challenge to manage patients with syphilis at the serofast stage using the recommended treatments.…”

Treatment monitoring in syphilis using the autoanalyser.

“…The automated tests were performed according to methods previously described (MacFarlane et al, 1976).…”