Molecular typing of Treponema pallidum isolated from patients attending the University Hospital of Buenos Aires, Argentina.

GALLO VAULET L; MIKALOVA L; GRILLOVA L; CASCO R; AVILA MM; RODRIGUEZ FERMEPÍN M; PANDO MA; SMAJS D

Congreso; 6th Congress of European Microbiologists; 2015

Background: Treponema pallidum subsp. pallidum, the causative agent ofsyphilis, is a sexually-transmitted disease with worldwide occurrence.Molecular typing of T. pallidum providesvaluable epidemiological information, including determination of macrolideresistance. Objectives: This study wasaimed to type, for the first time in South America, T. pallidum isolates in clinical samples.   Methods: During 2013, 79samples were collected from patiens with clinical signs of syphilis: 72 lesionswabs, 3 whole blood samples and 4 cerebrospinal fluid. DNA was extracted andPCR amplification of polA(TP0105), tmpC(TP0319), TP0136, TP0548, and 23SrRNA was performed(1). A CDC typing scheme was made including the determinationof 60-bp repeats in the arp gene,RFLP of tprE-G-J and sequence analysisof TP0548(2). The human MTHFR gene was amplified totest for PCR inhibitors.         Conclusions: TreponemalDNA was detected in 57.3%(43/75) of samples (four were excluded). A total of 36samples (83.7%) were typed. Nine genotypes were detected using thesequencing-based typing, with SSS being the most frequent. CDC typing schemewas done in 22 samples, and 7 genotypes were detected, with 14d/d being themost common. In 13.9% of the samples, mutations causing macrolide resistancewere detected. In conclusion, during this first molecular typing study, low frequencyof macrolide resistant mutations was detected compared to Europe and the US. Althoughsome detected treponemal genotypes were identical to those described in othercountries, several genotypes were new, not found outside Argentina.