Enhanced Therapy for Early Syphilis in patients with and without HIV infection
Debra Bynum, MD
September 9, 1997
Clinical Bottom Lines:
1) There was no difference in the rate of serologically defined treatment failure between patients treated for early syphilis with standard treatment (2.4 million units of Penicillin G benzathine) and patients treated with enhanced therapy (2.4 million units PCN G plus 10 day course of amoxicillin and probenicid) with an 18 % serological failure rate with standard therapy and 17% serological failure rate with enhanced therapy at 6 months.
2) Serologically defined treatment failures were more common among HIV patients with primary syphilis compared to non-HIV patients with primary syphilis. There was a trend toward more treatment failures in HIV patients with secondary or early latent syphilis, but these differences were not statistically significant.
3) Despite serological evidence of treatment failure, at one year of follow-up there was only one clinical treatment failure ( in an HIV patient) manifest as a new rash-- there were no cases of symptomatic neurosyphilis.
4) T. pallidum was found in the initial CSF of 24% of patients (32 of 131) and after treatment in 7 of 35 patients -- but there were no cases of clinical neurosyphilis and the detection of T. pallidum did not differ according to HIV status.
The Evidence:
Multicenter, randomized, double-blind trial comparing standard therapy with 2.4 million units of PCN G with therapy enhanced by 10 day course of amoxicillin and probenecid. A total of 541 patients were included, 440 without and 101 with HIV infection. Follow up was conducted over the course of one year for evidence of serologic and clinical treatment failure.
Treatment Failure |
Adjusted Odds |
||
Treatment |
|||
Standard |
28/157 (18%) |
1.1 (0.6-2.2) |
|
Enhanced |
29/169 (17%) |
1.0 |
|
Primary Syphilis |
|||
HIV |
4/18 (22%) |
7.6 ( 1.3-44.2) |
|
Non-HIV |
3/59 (5%) |
1.0 |
|
Secondary Syphilis |
|||
HIV |
8/35 (23%) |
2.9 (0.9-8.9) |
|
Non-HIV |
12/121 (10%) |
1.0 |
|
Early Latent |
|||
HIV |
3/16 (19%) |
0.4 (0.1-2.2) |
|
Non-HIV |
27/77 (35%) |
1.0 |
Comments:
1) Although it is reported that "serological failures were more common among HIV infected patients", this was only statistically significant in patients with primary (not secondary or early latent) syphilis.
2) Despite significant serological failure rates in both HIV and nonHIV patients, clinical failure was uncommon (regardless of HIV status)
3) The detection of T. pallidum in the CSF prior to treatment did not predict treatment failure (but only 131 patients had an LP prior to treatment and only 35 had an LP after treatment).
4) Follow up in this study was only for one year (and only 52% folllow up at one year).
Source: N Engl J Med 1997; 337: 307-14.