AT THE 2016 STD PREVENTION CONFERENCE
ATLANTA (FRONTLINE MEDICAL NEWS) – A multidose regimen of metronidazole was found to have a lower likelihood of treatment failure than a single-dose regimen in treating trichomoniasis in a meta-analysis presented at a conference on STD prevention sponsored by the Centers for Disease Control and Prevention.
In its 2015 STD treatment guidelines , the CDC recommends that women with HIV infection who receive a diagnosis of Trichomonas vaginalis infection should be treated with metronidazole 500 mg orally twice daily for 7 days, rather than with a 2-g single dose of metronidazole. However, it recommends a 2-g single dose of either metronidazole or tinidazole for other women with trichomoniasis as first-line treatment.
The new findings suggest that recommendation should be reexamined, Patricia Kissinger, PhD, a professor of epidemiology at Tulane University, New Orleans, said at the conference.
“[Trichomoniasis] is the most prevalent nonviral sexually transmitted infection in the U.S.; there are estimates of anywhere between 3.7 to 7 million [cases]. It eclipses gonorrhea, chlamydia, and syphilis in its prevalence, and there are about 276 million [cases] worldwide,” she said.
While single-dose therapy is inexpensive and has excellent adherence, recurrence has been a problem.
To compare the effectiveness of single- versus multidose treatment strategies, Dr. Kissinger and her coinvestigators searched Embase, Medline, and clinicaltrials.gov for any studies published before Jan. 25, 2016, that were English-language clinical trials evaluating trichomoniasis and metronidazole, and that compared single with multidose treatment regimens. Nearly 500 articles were identified and reviewed, but only six studies were included for analysis based on relevance and quality. Of those, one study included only HIV-positive women.
The primary endpoint was the pooled relative risk (RR) across all included studies of treatment failure in single- and multidose regimens.
Results showed that women who received single-dose metronidazole were 1.87 times more likely to experience treatment failure than those who received multidose therapy (95% confidence interval, 1.23-2.82; P less than .01). When the investigators excluded the one study involving HIV-positive women, the findings were similar, with those on single-dose therapy being 1.80 times more likely than those on a multidose regimen to experience treatment failure (95% CI, 1.07-3.02; P less than .03).
“Limitations [include] that the quality of the studies were not at the same level as we’d be doing in this decade,” Dr. Kissinger said. “There’s a scarcity of studies that evaluate this topic, [and] clinical trial methods have improved substantially since the 1980s, when most of these studies were done.”
Dr. Kissinger did not report information on financial disclosures.
