Typing of Treponema pallidum in a Brazilian sample and follow-up of treatment using molecular assays

• Published in: Brazilian journal of microbiology Vol. 55; no. 3; pp. 2101 - 2105
• Main Authors: Ferreira de Sá Queiroz, Júlio Henrique, Ferreira, Tiago da Silva, Soria Vieira Benedetti, Kelle Cristhiane, Danyelly da Costa Ribeiro, Anny, Omizolo de Souza, Ronaldo, Simionatto, Simone
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.09.2024; Springer Nature B.V
• Subjects: Adult; Amplification; Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Assaying; Azithromycin; Bacterial; Biomedical and Life Sciences; Blood; Blood levels; Brazil; Deoxyribonucleic acid; Diagnosis; Disease control; Disease resistance; Disease transmission; DNA; DNA, Bacterial - genetics; Doxycycline; Doxycycline - therapeutic use; Drug Resistance, Bacterial - genetics; Follow-Up Studies; Food Microbiology; Fungal and Virus Molecular Biology - Short Communication; Genotype; Genotypes; Humans; Lesions; Life Sciences; Macrolides - pharmacology; Male; Medical Microbiology; Microbial Ecology; Microbial Genetics and Genomics; Microbiology; Molecular Typing - methods; Mutation; Mycology; Public health; RNA, Ribosomal, 23S - genetics; rRNA; Sexually transmitted diseases; STD; Syphilis; Syphilis - diagnosis; Syphilis - drug therapy; Syphilis - microbiology; Treponema pallidum; Treponema pallidum - classification; Treponema pallidum - drug effects; Treponema pallidum - genetics; Treponema pallidum - isolation & purification; Brazil; Resistance; qPCR; ECDC typing; Treatment; Syphilis
• ISSN: 1517-8382; 1678-4405; 1678-4405
• DOI: 10.1007/s42770-024-01342-w

Syphilis remains a significant public health concern, with serological assays being the primary method for diagnosis. However, molecular techniques have proven to be reliable tools for the diagnosis and understanding of the transmission dynamics of Treponema pallidum infection. This study aimed to evaluate the efficacy of syphilis treatment using molecular assays, perform Enhanced Centers for Disease Control and Prevention (ECDC) typing, and analyze resistance (macrolide and doxycycline) in the T. pallidum isolate. PCR assay amplified treponemal DNA only from the lesion sample, whereas qPCR was able to amplify DNA in both lesion and blood samples before treatment. Throughout the treatment follow-up, qPCR effectively did not identify treponemal DNA in the blood for up to one to two weeks after treatment. ECDC typing revealed the genotype 14 e/g in the Brazilian T. pallidum isolate, and the presence of the A2058G mutation in 23 S rRNA gene, indicating macrolide resistance. Although, the G1058C mutation in 16 S rRNA gene was not detected. Notably, qPCR demonstrated its potential for diagnosing T. pallidum in blood samples, even when the treponemal DNA levels were low, enabling more accurate and sensitive diagnosis and guiding better syphilis therapy. In addition, to the best of our knowledge, this study represents the first identification of subtype 14 e/g and azithromycin resistance in a Brazilian T. pallidum isolate.