No Improvement in Serological Response among Serofast Latent Patients Retreated with Benzathine Penicillin

Persistent non-treponemal titres after treatment are common among patients with latent syphilis. Although retreatment is often done in clinical practice, optimal management remains uncertain due to the paucity of data regarding serological response to retreatment and long-term outcomes. We compared the serological responses of serofast latent syphilis patients retreated with 7.2 million units of benzathine penicillin with the responses of patients who did not receive retreatment (control group). We retrospectively analysed the serological response to therapy following retreatment of 35 serofast latent syphilis patients at 12 months with benzathine penicillin 2.4 million units weekly for 3 weeks. In all, 74.3% (26/35) of the cases with latent syphilis who failed to achieve serological cure at 12 months after initial therapy achieved serological cure after retreatment and after an additional 12 months of follow-up. However, statistically similar serological cure rate was observed in 80.0% (28/35) of the control group (p>.05). Our findings illustrate no improvement in serological response among serofast latent patients retreated with three doses of benzathine penicillin.