Efficacy of Doxycycline in the Treatment of Syphilis

Abstract

Doxycycline is an alternative antibiotic drug for the treatment of syphilis, but data on its efficacy, especially data on its efficacy against late latent syphilis, are limited. A retrospective study was conducted to evaluate the effectiveness of doxycycline for the treatment of patients with different stages of syphilis. Patients who received doxycycline treatment between June 2011 and June 2014 were involved. The serological response to doxycycline was defined as either a negative toluidine red unheated serum test (TRUST) result or a Ն4-fold decrease in titer at 12 months following the treatment. Univariate and multivariate logistic regression analyses were performed to identify factors associated with the serological response. During the study period, a total of 163 syphilis patients were treated with doxycycline, and 118 patients completed doxycycline treatment and the 12-month follow-up. Among the 118 patients, the serological response rate at 12 months was 100.0% (7/7) in patients with primary syphilis, 96.9% (62/64) in patients with secondary syphilis, 91.3% (21/23) in patients with early latent syphilis, and 79.2% (19/24) in patients with late latent syphilis. The total serological response rates were 92.4% (109/118) for preprotocol (PP) patients and 66.9% (109/163) for all intention-to-treat (ITT) patients. In multivariate analysis, patients who serologically responded at 12 months following treatment were positively associated with a higher baseline TRUST titer and an earlier syphilis stage than nonresponders. Our study showed excellent treatment outcomes in patients with different stages of syphilis. Our data, along with those from other reports, support the usage of doxycycline as a good alternative therapeutic option in the treatment of syphilis.

In silico Potential of Approved Antimalarial Drugs for Repurposing Against COVID-19

“…MMPs are known to associate with several pathological conditions, such as rheumatoid arthritis, tumor invasion, multiple sclerosis (Marten and Zhou, 2005), syphlis (Dai et al, 2017), cardiovascular, neurological, and skin disorder (Griffin et al, 2010). MMPs are a family of zinc endopeptidases that play a vital role in interaction between viral protein and host receptor and fusion (Phillips et al, 2017), degrade proteins of extracellular matrix leading to production of inflammatory cytokines.…”

The resurgence of syphilis in high-income countries in the 2000s: a focus on Europe

“…The European syphilis management guideline recommends intramuscular procaine penicillin for 10–14 days as second-line therapy option if benzathine penicillin G is not available with additional options, such as doxycycline, ceftriaxone or azithromycin, in case of bleeding disorders, penicillin allergy or refusal of parenteral treatment [44]. All three alternatives are effective; however, a recent meta-analysis found that doxycycline/tetracycline recipients had a higher treatment failure rate than those treated with benzathine penicillin G [46–50]. In addition, azithromycin resistance and treatment failures have been described in the USA, Europe, Australia, China and elsewhere and azithromycin should therefore only be used as a last resort and when treatment can be followed up closely [6, 44, 51].…”

Efficacy of linezolid on Treponema pallidum, the syphilis agent: A preclinical study

“…However, only three randomized clinical trials have compared penicillin to other antibiotics (i.e., ceftriaxone and azithromycin) [20] , [21] , [22] . Conversely, the efficacy of doxycycline, the second-line treatment for syphilis, is mainly supported by two prospective studies [ 23 , 24 ] and other small retrospective studies [25] , [26] , [27] .…”