How to manage a patient with a history of treated syphilis who now has a reactive RPR (Rapid Plasma Reagin) and reactive Treponema pallidum Antibodies?

From the Guidelines

The patient with a history of treated syphilis who now has a reactive RPR and reactive Treponema pallidum antibodies should be evaluated for reinfection or treatment failure, and if the RPR titer has increased fourfold or more, retreatment with benzathine penicillin G is recommended. To determine the appropriate course of action, it is essential to compare the current RPR titer with previous results. If the titer has increased fourfold or more, this suggests reinfection or treatment failure requiring retreatment 1. The recommended regimen is benzathine penicillin G 2.4 million units intramuscularly once weekly for three weeks (total 7.2 million units) for late latent syphilis or syphilis of unknown duration. For early syphilis (primary, secondary, or early latent), a single dose of benzathine penicillin G 2.4 million units intramuscularly is sufficient.

Some key points to consider in the management of this patient include:

• If the patient is penicillin-allergic, doxycycline 100 mg orally twice daily for 14 days (early syphilis) or 28 days (late syphilis) can be used as an alternative treatment 1.
• If the RPR titer has remained stable or decreased compared to previous results, this likely represents a serofast state, where antibodies persist despite adequate treatment, and no retreatment is necessary, but clinical monitoring should continue.
• Treponema pallidum antibodies typically remain positive for life regardless of treatment, while non-treponemal tests like RPR may eventually become negative or remain positive at a low, stable titer.
• Sexual partners should be evaluated and treated if there's concern for reinfection, and HIV testing should be performed if not recently done.

It is crucial to note that the patient's current RPR titer is 1:32, which is a significant increase from the previous result, suggesting possible reinfection or treatment failure. Therefore, re-treatment with benzathine penicillin G is recommended, and the patient should be closely monitored for any signs of treatment failure or reinfection 1.

From the FDA Drug Label

In venereal disease, when co-existent syphilis is suspected, dark field examinations should be done before treatment is started and the blood serology repeated monthly for at least 4 months.

The patient's reactive RPR and reactive Treponema pallidum Antibodies suggest possible syphilis re-infection or persistent infection.

• Re-treatment may be necessary, and the patient should be evaluated for co-existent syphilis.
• Dark field examinations and blood serology should be repeated monthly for at least 4 months to monitor the patient's response to treatment 2.
• The patient should be counseled on the risks of re-infection and the importance of safe sex practices.

From the Research

Management of Patient with History of Treated Syphilis

• The patient has a history of treated syphilis in 2019 and now presents with a reactive RPR and reactive Treponema pallidum Antibodies.
• The current lab results show:
  • RPR: Reactive
  • RPR Quant: 1:32
  • Treponema pallidum Antibodies: Reactive
• The management of this patient should be based on the current guidelines for the treatment of syphilis.

Treatment Options

• According to the studies 3, 4, 5, 6, doxycycline and benzathine penicillin G are effective treatments for early syphilis.
• A study 7 found that single-dose benzathine penicillin G plus doxycycline achieved higher serologic responses than single-dose benzathine penicillin G alone in people with HIV.
• However, the patient's current situation is not directly addressed in these studies, as they focus on the treatment of early syphilis rather than the management of a patient with a history of treated syphilis.

Serological Response

• The patient's reactive RPR and Treponema pallidum Antibodies indicate a potential serological response to a previous infection.
• The studies 3, 4, 5, 6 demonstrate the efficacy of doxycycline and benzathine penicillin G in achieving serological responses in patients with early syphilis.
• The study 7 highlights the importance of considering the patient's HIV status when selecting a treatment regimen.

Next Steps

• Further evaluation and consultation with a healthcare professional are necessary to determine the best course of action for this patient.
• The patient's medical history, current symptoms, and laboratory results should be carefully considered when developing a treatment plan.
• The use of doxycycline or benzathine penicillin G, alone or in combination, may be considered based on the patient's specific needs and medical history, as suggested by the studies 3, 4, 5, 6, 7.