Screening for Syphilis Incidence in a Tertiary Care Facility: A Reverse Algorithm Cross-Sectional Investigation

Pratheesh, Anna; Gopinathan, Anusha; Datchanamoorthy, Maheswary; SS, Jayalakshmi; Sivankutty Nair, Aparna; Kakithakara Vajravelu, Leela

year 20, Issue 1 (January - February 2026) Iran J Med Microbiol 2026, 20(1): 56-62 | Back to browse issues page

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Pratheesh A, Gopinathan A, Datchanamoorthy M, SS J, Sivankutty Nair A, Kakithakara Vajravelu L. Screening for Syphilis Incidence in a Tertiary Care Facility: A Reverse Algorithm Cross-Sectional Investigation. Iran J Med Microbiol 2026; 20 (1) :56-62
URL: http://ijmm.ir/article-1-2888-en.html

Screening for Syphilis Incidence in a Tertiary Care Facility: A Reverse Algorithm Cross-Sectional Investigation

Anna Pratheesh¹

, Anusha Gopinathan²

, Maheswary Datchanamoorthy¹

, Jayalakshmi SS¹

, Aparna Sivankutty Nair¹

, Leela Kakithakara Vajravelu¹

1- Department of Microbiology, SRM Medical College Hospital & Research Center, SRM Institute of Science and Technology, Kattankulathur, India
2- Department of Microbiology, SRM Medical College Hospital & Research Center, SRM Institute of Science and Technology, Kattankulathur, India , anusha.gopinathan@gmail.com

Abstract: (134 Views)

Background and Aim: Syphilis continues to present a major public health challenge globally, with serologic testing central to detection and control efforts. Comparative evaluation of screening algorithms, particularly the performance of automated Chemiluminescent Microparticle Immunoassay (CMIA) versus Rapid plasma reagin (RPR) using Treponema (T.) pallidum hemagglutination assay (TPHA) as the reference standard, is critical for optimizing diagnostic accuracy. This study aimed to investigate syphilis prevalence and assesse the efficacy of reverse screening strategies in a high-volume academic tertiary care center.
Materials and Methods: The study was conducted from July 2024 to March 2025 at SRM Medical College Hospital and Research Centre. Individuals presenting to the outpatient department were screened using Abbott ARCHITECT Syphilis TP (CMIA). Positive samples underwent RPR testing, followed by TPHA confirmation.
Results & Conclusion: Out of 4312 samples, 52 (1.2%) were CMIA positive. Among these, 75% were male and 25% were female, with one case of congenital syphilis. Of the CMIA-positive cases, 35 (67.3%) were RPR positive and 34 (32.7%) were TPHA confirmed. Among the 17 RPR-negative samples, 4 (23.52%) were TPHA positive and 13 (76.48%) were negative. The study found low syphilis prevalence (1.2%) among the screened population. A significant proportion of RPR-negative but TPHA-positive cases underscore the need for combined testing strategies. These findings highlight the importance of comprehensive serologic screening, continued surveillance, and targeted public health interventions.

Keywords: Chemiluminescent Microparticle Immunoassay, Hemagglutination assay, Rapid Plasma Reagin, Syphilis, Treponema pallidum

Full-Text [PDF 442 kb] (18 Downloads)

Type of Study: Brief Original Article | Subject: Medical Bacteriology
Received: 2025/11/17 | Accepted: 2026/02/20 | ePublished: 2026/02/28

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