Comparison of Quantitative Results among Two Automated Rapid Plasma Reagin (RPR) Assays and a Manual RPR Test.
10.3343/kjlm.2009.29.4.331
- Author:
Yeong Sic KIM
1
;
Jehoon LEE
;
Hae Kyung LEE
;
Hyunjung KIM
;
Hi Jeong KWON
;
Ki Ouk MIN
;
Eun Joo SEO
;
Soo Young KIM
Author Information
1. Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea. vsykim@catholic.ac.kr
- Publication Type:Original Article ; Comparative Study ; English Abstract
- Keywords:
Rapid Plasma Reagin;
RPR titer;
Prozone effect
- MeSH:
Automation;
Female;
Humans;
Male;
Reagent Kits, Diagnostic;
Reagins/*blood;
Sensitivity and Specificity;
Syphilis/*diagnosis;
Syphilis Serodiagnosis/*methods;
Treponema pallidum
- From:The Korean Journal of Laboratory Medicine
2009;29(4):331-337
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: We compared two automated Rapid Plasma Reagin (RPR) assay kits with a manual RPR assay kit to evaluate the possibility of using the two automated RPR assays as an alternative to the manual RPR assay for a quantitative monitoring. METHODS: One hundred eighty-five samples were analyzed, including 16 sera from patients with primary, secondary, and latent syphilis. Measured RPR unit (R.U.) values of two automated RPR assay kits, Mediace RPR (Sekisui Chemical Co., Ltd, Japan) and HBi Auto RPR (HBI Co., Ltd, Korea), were compared with the RPR titers of Macro-Vue RPR card test (Becton Dickinson BD Microbiology systems, USA). As a confirmatory test, Anti-Treponema pallidum EUROLINE WB (IgG) and Anti-Treponema pallidum EUROLINE WB (IgM) (Euroimmun, Germany) were used. RESULTS: There was a prozone effect with Mediace RPR at RPR titer (card test) of 1:16, but not with HBi Auto RPR. The R.U. values of the two automated RPR assays did not show proportional increase to the RPR titer. Agreement between manual RPR and two automated RPR assay kits, Mediace RPR assay and HBi Auto RPR assay, were 83.8% and 83.2%, respectively. CONCLUSIONS: The two automated RPR assay kits could not be used as an alternative to manual RPR test for quantitative analysis of RPR titer. As Mediace RPR shows a prozone effect at relatively low RPR titer, caution is needed in the interpretation of the measured values.
