Science and Technology Production

Medicina - Development of real time PCR based protocols for syphilis diagnosis based on tpp47 and pola gens in young adult’s patients

Congress

Authorship:

García LN ; Fernandez Pardal P ; Gonzalez N ; Satostegui M ; Moscatelli, G ; Lascano F ; Warszatska B ; Bocassi A ; Leiro V ; Altcheh J

Date:

2023

Publishing House and Editing Place:

Medicina

Summary *

Syphilis is caused by Treponema pallidum pallidum (TPA) and continues afflicting 6 million people annually including 1 million pregnant women. Despite the existence of effective treatments, during recent decade’s cases have increased affecting disproportionately young women causing impact on the congenital syphilis rates and direct costs. There are public initiatives addressing the serological diagnosis tests to reducing syphilis incidence but there are still insufficient. The use of molecular biology techniques (MBT) in the diagnosis of TPA is in the beginnings. We collaborated in an international study evaluating MBT for the diagnosis of syphilis in young adult’s patients with syphilis. Our aim was the performance of real time PCR (qPCR) in blood and swab samples for the detection of tpp47and pola gens and explore TPA results among clinical stage and samples sources. We incorporated 95 cases of acquired syphilis transmitted through sexual contact and 272 samples were processed for DNA extraction (QIAGEN, Germany) followed by qPCR using Taqman probes in a CFX 96 equipment (Bio-Rad, USA). Among demographic, media (IQ1-IQ3) characteristics was: 28 years old (22-35) and VDRL results: 64 (32-128), previous syphilis diagnosis was 1(1-2) and the numbers of sexual partners were 2(1-3). The % of women as well as HIV patients was 23%. The qPCR efficiency per patient for tpp47 in swabs was: Sensitivity (Se)=86.3, Specificity(Sp)=100, Positive predictive value(PPV)=100, Negative predictive value(NPV) = 60.5; with lowest values in blood samples (16/100/100/24). For pola the values were: Se=85.4,Sp= 100, PPV= 100,NPV= 62.2 and for blood samples (17/100/100/24.3). Notably, the Se in normal oral mucosa´ swabs from secondary stage patients was 70%. These preliminary data support the use of qPCR methods as confirmatory techniques in blood samples and for screening in swab samples in syphilis diagnosis algorithm. Which could improve prevention policies for congenital syphilis cases. Information provided by the agent in SIGEVA

Key Words

real time PCRdiagnosissyphilisoral mucosa