Serological diagnosis of culture confirmed early Lyme disease (erythema migrans) by two different EIAs and three Western Blot tests in an Italian population
Abstract number: 1134_01_105
Sparacino M., Marangoni A., Cavrini F., Storni E., Cevenini R., Mondardini V., Sambri V.
To comparatively evaluate the performances of two different EIA methods and three Western blot tests for the diagnosis of Lyme borreliosis.
60 sera were serially obtained from 30 Italian patients suffering from acute culture confirmed Lyme disease. All the patients received antimicrobial therapy at the enrollment: the follow up period was 1 month. 65 cross-reacting serum specimens were also evaluated. The following EIAs were used: Anti-Borrelia plus VlsE (Euroimmun) and Quick ELISA C6 (synthetic peptide based from Immunetics). As confirmatory methods, three different Western blot (WB) tests were used: Euroline-WB (Euroimmun), Qualicode B.burgdorferi WB (Immunetics) and a multispecies home made test.
The highest sensitivity was found for Anti-Borrelia plus VlsE IgG (56.6%) whereas the sensitivity of Quick C6 was lower (33.3%). In addition, since 17 sera from the very early disease were positive only for the IgM response when tested by Anti-Borrelia plus VlsE IgM, this test performed as a whole system with a sensitivity of 85.0%. The specificity of Anti-Borrelia plus VlsE was 98.5% for the IgG and 78.5% for the IgM: these values suggested the need of a confirmatory testing by WB. The three WB methods showed comparable performances for the detection of the IgM. On the other hand, the WBs performed differently for the IgG detection: the most sensitive was the home made method (71.7%), ranking at second place is the Euroline-WB (68.3%). The Qualicode test was the least sensitive (26.6%). The specificity of the home made and of Qualicode tests was 100%, whereas the Euroline WB IgG identified 12 cross-reacting specimens as border line, giving a specificity value of 80.0%.
The Anti-Borrelia plus VlsE ELISA showed to be a better test than the Quick C6 but it still need to be followed by a confirmatory test in any case of positivity. The need of WB still remains in Europe, where the etiology of Lyme disease is complicated by more than one pathogenic genospecies.
|Session name:||XXIst ISTH Congress|
|Back to top|