Lab Med Online.  2014 Jan;4(1):36-42.

Establishment and Multicenter Evaluation of a National Reference Panel for Syphilis Antibodies in Korea

• Huh HJ
• Chae SL
• Oh DJ
• Park Q
• Lim CS
• Um TH
• Park YM
• Cha YJ

Abstract

BACKGROUND
Establishment of a national reference panel for syphilis antibodies is necessary to evaluate the performance of in-vitro diagnostic tests for syphilis and to verify test quality. This study aimed to establish a national reference panel for syphilis antibodies, to assess the suitability of a panel for non-treponemal and treponemal testing, and to assess the reactivity of the various tests currently in use.
METHODS
Treponemal pallidum particle agglutination (TPPA)-positive and -negative fresh frozen plasma samples were obtained. After the fresh frozen plasma was converted to serum by defibrination, the samples were pooled. Two candidate reference standards containing no syphilis antibodies and 10 candidate reference standards containing syphilis antibodies were prepared on the basis of reactivity in the TPPA assay. Candidate reference standards were tested by three laboratories using five non-treponemal tests and four treponemal tests.
RESULTS
All three laboratories reported positive non-treponemal test results for the mixed-titer performance panel (MP)/6-MP/12. MP/1, MP/2, and MP/3 were negative for non-treponemal tests. MP/4 and MP/5 were reported either as positive or negative according to the laboratories. All laboratories reported positive TPPA results for MP/3-MP/12 and negative results for MP/1 and MP/2. No significant difference was detected among the treponemal testing results in three laboratories.
CONCLUSIONS
We established 12 candidate national reference standards containing various concentrations of syphilis antibodies. A collaborative study using nine tests demonstrated that 12 candidate national reference standards presented consistent results, except a few assays with low sensitivity, and thus could be used as a national reference panel for syphilis antibody testing.

Keyword

Syphilis; National reference standard; Reference panel; Treponemal test; Non-treponemal test

MeSH Terms

Agglutination
Antibodies*
Diagnostic Tests, Routine
Korea*
Plasma
Syphilis*
Antibodies

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