Background The direct detection of Treponema pallidum peptides in bodily fluids could facilitate the early diagnosis of initial-, repeat-, congenital- and neuro-syphilis.

Methods To this end, we prospectively recruited 54 individuals with a new diagnosis of syphilis and 6 controls. Their urine specimens were pooled according to disease stage and assessed using complementary mass spectrometry techniques (MALDI-TOF-TOFMS/MS, LC/ESI-IM-Q-TOF/HDMS^E) to uncover potential syphilis biomarkers.

Results In total, 26 unique peptides were uncovered corresponding to four unique T. pallidum proteins (Tp0486, Tp0742, Tp0804 and Tp0369) that have no, or minimal, genetic sequence similarity to other known proteins, including prokaryotes and human proteins.

Conclusion This is the first study reporting direct detection of T. pallidum proteins in human biofluid samples using MS-based proteomics methods. These could be promising diagnostic test targets.

Disclosure No significant relationships.