When should treatment be started for the sexual partners of a patient diagnosed with syphilis?

When to Initiate Treatment for Partners of Patients with Syphilis

Immediate Presumptive Treatment (Within 90 Days of Exposure)

Sexual partners exposed within 90 days before the diagnosis of primary, secondary, or early latent syphilis should receive immediate presumptive treatment with benzathine penicillin G 2.4 million units IM as a single dose, even if their serologic tests are negative. 1, 2, 3

This recommendation is critical because:

• Early infection may not yet produce detectable antibodies, making seronegative partners potentially infected but not yet showing serologic evidence of disease 2
• Immediate treatment prevents progression to later stages that cause significant morbidity and mortality 2
• The same single-dose benzathine penicillin G regimen used for primary and secondary syphilis is appropriate for exposed partners 1, 2

Treatment Based on Exposure Timing Beyond 90 Days

For partners exposed more than 90 days before diagnosis, the approach depends on test availability and follow-up certainty:

• Treat presumptively if serologic results are not immediately available or if the opportunity for follow-up is uncertain 1, 3
• If serologic testing is available and follow-up is assured, treatment should be based on the test results 1, 3

Stage-Specific Partner Identification Periods

The time periods for identifying at-risk partners vary by stage of the index patient's infection:

• Primary syphilis: Identify partners from 3 months plus duration of symptoms before treatment 1, 2, 3
• Secondary syphilis: Identify partners from 6 months plus duration of symptoms before treatment 1, 2, 3
• Early latent syphilis: Identify partners from 1 year before treatment 1, 2, 3

Special Consideration for High-Titer Patients

For patients with syphilis of unknown duration who have high nontreponemal serologic test titers (≥1:32), assume early syphilis for purposes of partner notification and presumptive treatment. 1

This means their partners should be managed according to the early syphilis algorithm above, with presumptive treatment for those exposed within 90 days.

Long-Term Partners of Latent Syphilis Patients

Long-term sex partners of patients with latent syphilis should be evaluated clinically and serologically, then treated based on their evaluation findings rather than presumptively 1

Critical Management Components

Treatment Regimen for Partners

• First-line: Benzathine penicillin G 2.4 million units IM in a single dose 1, 2
• Penicillin-allergic patients: Doxycycline 100 mg orally twice daily for 14 days 2, 3
• Alternative for penicillin allergy: Tetracycline 500 mg orally four times daily for 14 days (though compliance is typically lower) 2

Essential Follow-Up Requirements

All treated partners require repeat serologic testing (RPR or VDRL) at 6,12, and 24 weeks after exposure, as initial negative tests do not exclude early infection 2

HIV Testing Mandate

All patients with syphilis and their partners must be tested for HIV, as co-infection is common and influences management 1, 2, 3, 4

Important Caveats

Jarisch-Herxheimer Reaction

Counsel all partners before treatment about the Jarisch-Herxheimer reaction, an acute febrile reaction with headache and myalgia that may occur within 24 hours of treatment 2, 3, 5

• Antipyretics may provide symptomatic relief but do not prevent the reaction 1
• In pregnant partners, this reaction can precipitate early labor or fetal distress, but therapy should not be delayed 1, 3

Pitfall to Avoid

Do not use serologic titers alone to differentiate early from late latent syphilis when determining partner treatment approach 2

The key principle is aggressive, early intervention for recently exposed partners to interrupt transmission chains and prevent disease progression, with the 90-day threshold serving as the critical decision point for presumptive versus test-based treatment.