High-dose oral amoxicillin plus probenecid is highly effective for syphilis in patients with HIV infection.

Abstract

BACKGROUND:

Intramuscular benzathine penicillin G (BPG) is widely used for the treatment of syphilis. However, BPG is not available in some countries. This study examined the effectiveness and safety of high-dose oral amoxicillin plus probenecid for the treatment of syphilis in patients with human immunodeficiency virus type 1 (HIV-1).

METHODS:

This retrospective observational study included 286 HIV-infected male patients with syphilis (median age, 36 years; median CD4 count, 389 cells/µL) who were treated with oral amoxicillin 3 g plus probenecid. Syphilis was diagnosed by both serum rapid plasma reagin (RPR) titers ≥8 and positive Treponema pallidum hemagglutination test. Patients with neurosyphilis diagnosed by cerebrospinal fluid examination were excluded. Successful treatment was defined as a at least 4-fold decrement in RPR titer.

RESULTS:

The overall treatment efficacy was 95.5% (95% confidence interval [CI], 92.4%-97.7%; 273/286 patients), and efficacy for primary, secondary, early latent, late latent, and unknown duration syphilis was 93.8% (95% CI, 68.1%-99.8%; 15/16), 97.3% (95% CI, 92.9%-99.2%; 142/146), 100% (95% CI, 90.5%-100%; 37/37), 85.7% (95% CI, 58.6%-96.4%; 18/21), and 92.4% (95% CI, 81.9%-97.3%; 61/66), respectively. Treatment duration was mostly 14-16 days (49.7%) or 28-30 days (34.3%), with efficacy of 94.4% (134/142) and 95.9% (94/98), respectively; 96.3% of successfully treated patients achieved a ≥4-fold decrement in RPR titer within 12 months. Adverse events were noted in 28 (9.8%) patients, and 25 of these (89.3%) were successfully treated. Only 6% of patients underwent lumbar puncture.

CONCLUSIONS:

The combination of oral amoxicillin 3 g plus probenecid was highly effective and tolerable for the treatment of syphilis in patients with HIV-1 infection.

• Authors: Ryutaro Tanizaki, Takeshi Nishijima, Takahiro Aoki, Katsuji Teruya, Yoshimi Kikuchi, Shinichi Oka, Hiroyuki Gatanaga
• Journal: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America (Clin Infect Dis) Vol. 61 Issue 2 Pg. 177-83 (Jul 15 2015) ISSN: 1537-6591 [Electronic] United States
• PMID: 25829004 (Publication Type: Journal Article, Observational Study, Research Support, Non-U.S. Gov't)
• Copyright: © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: [email protected].

Chemical References

• Anti-Bacterial Agents
• Amoxicillin
• Probenecid

Topics

• Administration, Oral
• Adult
• Amoxicillin (administration & dosage, adverse effects, therapeutic use)
• Anti-Bacterial Agents (administration & dosage)
• CD4 Lymphocyte Count
• Drug Therapy, Combination
• HIV Infections (complications)
• Humans
• Male
• Probenecid (administration & dosage, adverse effects, therapeutic use)
• Retrospective Studies
• Risk Factors
• Syphilis (complications, diagnosis, drug therapy, immunology, prevention & control)
• Syphilis Serodiagnosis
• Treatment Outcome
• Young Adult