Related Experiment Video
Updated: Jul 10, 2026

Procedures for In Vitro Cultivation of Treponema pallidum, the Syphilis Spirochete
Published on: January 24, 2025
Clinical case of seroconversion for syphilis following a needlestick injury: why not take a prophylaxis?
Alfredo Franco1, Lucia Aprea, Chiara Dell'Isola
1Infectious Diseases Hospital D. Cotugno, Naples, Italy.
Abstract:
A 47-year-old woman was pricked accidentally with a needle previously used for a neurosyphilitic man. At day 0 she had no positive laboratory results for the infection, while the source, at day 1, had TPHA positive, but no post-exposure prophylaxis (PEP) against syphilis was prescribed. The subject missed the day 30 follow-up, and underwent our visit at day 90, when she showed no clinical signs, but she seroconverted (VDRL = positive 1/2; TPHA = positive 1/320; FTA-Abs IgG and IgM = present). She started antibiotic therapy, and currently her serological status is VDRL = positive 1/2, TPHA = positive 1/160, FTA-Abs IgM = negative.
Related Concept Videos
Sexually Transmitted Infections
Rocky Mountain Spotted Fever
Genital Herpes
Smallpox
Streptococcal Pharyngitis
Infection
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...
