Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia

Introduction: The global incidence of syphilis increased drastically throughout the world, including Malaysia. Screening algorithm with high sensitivity and specificity should be available to detect syphilis accurately. This study aimed to assess the performance of reverse screening algorithm for...

Full description

Bibliographic Details
Main Author: Sidek, Nurul Azira
Format: Thesis
Language:English
Published: 2021
Subjects:
Online Access:http://eprints.usm.my/60611/
http://eprints.usm.my/60611/1/NURUL%20AZIRA%20BINTI%20SIDEK-E.pdf
_version_ 1848884493686931456
author Sidek, Nurul Azira
author_facet Sidek, Nurul Azira
author_sort Sidek, Nurul Azira
building USM Institutional Repository
collection Online Access
description Introduction: The global incidence of syphilis increased drastically throughout the world, including Malaysia. Screening algorithm with high sensitivity and specificity should be available to detect syphilis accurately. This study aimed to assess the performance of reverse screening algorithm for syphilis diagnosis in our population. We compare the diagnostic accuracy between two available screening methods: electrochemiluminescence immunoassay (ECLIA) and rapid plasma reagin (RPR), each represents reverse and traditional screening algorithms, respectively. Materials and methods: A total of 206 serum samples were included in this study. These samples were tested with ECLIA, RPR, and Treponema pallidum particle agglutination (TPPA) assay. TPPA was considered as the gold standard test. Reverse and traditional screening algorithms were applied to all specimens. Sensitivity, specificity and predictive values of the screening tests were calculated. ROC curve analysis was used to determine optimal cut-off RPR titer related to TPPA reactivity. Results: Out of 206 serum samples, 32 (15.53%) were diagnosed with syphilis using the reverse algorithm, but only 23 (11.17%) were diagnosed with syphilis using the traditional algorithm. Majority of syphilis cases were male and among  50 years age group. Following the reverse algorithm, 27 (13.11%) cases showed discordant ECLIA and RPR results. Further testing with TPPA reveals that 5 (2.42%) cases are false positive ECLIA. The sensitivity, specificity, PPV and NPV of ECLIA and RPR for syphilis detection were 100%, 97.13%, 86.49%, 100%, and 71.88%, 92.53%, 63.89%, 94.71% respectively. Conclusion: The reverse algorithm showed better performance with higher syphilis detection. ECLIA revealed excellent diagnostic accuracy as a screening test for syphilis with a low false positivity supporting its use in our population. RPR reactivity (titer ≥1:1) should be able to predict the reactivity of confirmatory treponemal test. However, further evaluation with a larger sample size is required.
first_indexed 2025-11-15T19:07:35Z
format Thesis
id usm-60611
institution Universiti Sains Malaysia
institution_category Local University
language English
last_indexed 2025-11-15T19:07:35Z
publishDate 2021
recordtype eprints
repository_type Digital Repository
spelling usm-606112024-07-03T03:48:13Z http://eprints.usm.my/60611/ Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia Sidek, Nurul Azira R Medicine RA440-440.87 Study and teaching. Research Introduction: The global incidence of syphilis increased drastically throughout the world, including Malaysia. Screening algorithm with high sensitivity and specificity should be available to detect syphilis accurately. This study aimed to assess the performance of reverse screening algorithm for syphilis diagnosis in our population. We compare the diagnostic accuracy between two available screening methods: electrochemiluminescence immunoassay (ECLIA) and rapid plasma reagin (RPR), each represents reverse and traditional screening algorithms, respectively. Materials and methods: A total of 206 serum samples were included in this study. These samples were tested with ECLIA, RPR, and Treponema pallidum particle agglutination (TPPA) assay. TPPA was considered as the gold standard test. Reverse and traditional screening algorithms were applied to all specimens. Sensitivity, specificity and predictive values of the screening tests were calculated. ROC curve analysis was used to determine optimal cut-off RPR titer related to TPPA reactivity. Results: Out of 206 serum samples, 32 (15.53%) were diagnosed with syphilis using the reverse algorithm, but only 23 (11.17%) were diagnosed with syphilis using the traditional algorithm. Majority of syphilis cases were male and among  50 years age group. Following the reverse algorithm, 27 (13.11%) cases showed discordant ECLIA and RPR results. Further testing with TPPA reveals that 5 (2.42%) cases are false positive ECLIA. The sensitivity, specificity, PPV and NPV of ECLIA and RPR for syphilis detection were 100%, 97.13%, 86.49%, 100%, and 71.88%, 92.53%, 63.89%, 94.71% respectively. Conclusion: The reverse algorithm showed better performance with higher syphilis detection. ECLIA revealed excellent diagnostic accuracy as a screening test for syphilis with a low false positivity supporting its use in our population. RPR reactivity (titer ≥1:1) should be able to predict the reactivity of confirmatory treponemal test. However, further evaluation with a larger sample size is required. 2021 Thesis NonPeerReviewed application/pdf en http://eprints.usm.my/60611/1/NURUL%20AZIRA%20BINTI%20SIDEK-E.pdf Sidek, Nurul Azira (2021) Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia. Masters thesis, Universiti Sains Malaysia.
spellingShingle R Medicine
RA440-440.87 Study and teaching. Research
Sidek, Nurul Azira
Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia
title Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia
title_full Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia
title_fullStr Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia
title_full_unstemmed Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia
title_short Comparison between reverse and traditional screening algorithms for syphilis diagnosis in Hospital Universiti Sains Malaysia
title_sort comparison between reverse and traditional screening algorithms for syphilis diagnosis in hospital universiti sains malaysia
topic R Medicine
RA440-440.87 Study and teaching. Research
url http://eprints.usm.my/60611/
http://eprints.usm.my/60611/1/NURUL%20AZIRA%20BINTI%20SIDEK-E.pdf