UK Health Officials Aim to Stop the Emerging Superbug Mycoplasma Genitalium

Better diagnostics and treatment are needed for Mycoplasma genitalium—a lesser-known sexually-transmitted infection estimated to infect up to 3% of the population in many countries.

Mycoplasma genitalium (MG) is an emerging sexually-transmitted superbug and in an effort to stem the problem, health officials in the United Kingdom have recently passed new guidelines.

First identified in the early 1980s, M. genitalium is a bacterial pathogen which causes urethritis in males. According to the Centers for Disease Control and Prevention, it causes an estimated 15% to 20% of nongonococcal urethritis (NGU) cases, 20% to 25% of nonchlamydial NGU, and about 30% of persistent or recurrent urethritis. While MG can be asymptomatic, symptoms in men may include watery discharge from the penis and a burning sensation when urinating. In women, it can also cause discharge and urination discomfort, along with bleeding between periods, often after sexual intercourse. Cases left untreated in women can lead to pelvic inflammatory disease and fallopian tube scarring, potentially resulting in infertility. Over time, it can also cause inflammation leading to higher susceptibility to other sexually transmitted infections. These infections affect an estimated 1% to 3% of men and women in the United Kingdom, the United States, and Australia.

Cases of MG-related urethritis treated with a 7-day doxycycline regimen have a median cure rate of just 31%; trials have shown that a single dose of azithromycin, a macrolide, is significantly more effective against these infections. Increasingly, however, the pathogen has shown resistance to the macrolide class of antibiotics, with macrolide-resistant phenotypes making up more than 40% of cases in Europe, Japan, and the United States. The problem recently prompted the British Association of Sexual Health and HIV (BASHH) to issue new national guidelines for the management of MG infections. According to a survey conducted by BASHH, 72% of sexual health experts stress that if current practices do not change, MG will become a superbug, resistant to first- and second-line antibiotics, within the next 10 years.

Testing for MG has been difficult in the past, as M. genitalium is slow-growing and culture can take up to 6 months. As a result, the infections are often misdiagnosed as chlamydia, and as such, patients are treated with an improper antibiotic, which fuels resistance in M. genitalium. The new BASHH guidelines call for proper diagnosing of patients presenting with common MG symptoms—using the faster but more expensive MG diagnostic nucleic acid amplification tests (NAATs)—and treatment with the correct antibiotics.

“These new guidelines have been developed because we can’t afford to continue with the approach we have followed for the past 15 years as this will undoubtedly lead to a public health emergency with the emergence of MG as a superbug,” said BASHH spokesperson Paddy Horner, MD, in a recent statement. The new report highlights the problem of limited funding at UK clinics, which restricts the ability to purchase the testing tools needed to detect MG and deliver better patient care.

“Resources are urgently needed to ensure that diagnostic and antimicrobial resistance testing is available for women with the condition who are at high risk of infertility,” Dr Horner stressed. “We are asking the government directly to make this funding available to prevent a public health emergency waiting to happen and which is already spiraling out of control”.

Of 169 sexual health experts recently surveyed by BASHH, 64% reported a decrease of their most recent local sexual health budget, 83% admitted that they do not routinely test for MG in symptomatic patients, and 60% cited a lack of funding or resources. The new guidelines come as spending on sexual health services in UK local clinics has fallen by 10% in the last 4 years.