Evaluation of a point-of-care assay for the diagnosis of Trichomonas vaginalis in women at high risk for HIV infection

Investigator: Sheila Nabweyambo, BSc, MS

Location(s): Uganda

Parent Project: UCSF-Gladstone Center for AIDS Research (CFAR)


Trichomoniasis, caused by the protozoan parasite, Trichomonas vaginalis (TV), is the most common, curable sexually transmitted infection worldwide with a particularly high prevalence of up to 35% among women in Sub-Saharan Africa (SSA). This region of the world is also home to almost 70% of new human immunodeficiency virus (HIV) infections occurring worldwide and most of these infections occur in women. Recent studies showed that TV infection in African women is associated with a 1.5 ? 2.7-fold increased risk for HIV infection. Hence, trichomoniasis might be an important disease that is fuelling the HIV epidemic among women in SSA. Infection with TV is easily treatable with a single dose of antibiotics, however trichomoniasis remains asymptomatic in around 50% of cases in women. Hence accurate diagnosis of TV requires appropriate laboratory investigations. Currently, the most used method for TV diagnosis is wet-mount microscopy. Unfortunately, due to low sensitivity this test can miss up to 40% of TV infections. Highly sensitive nucleic acid amplification tests (NAATs) are now commercially available, however the platform is complex and difficult to implement in a rural resource-limited setting. A novel polymerase chain reaction (PCR) technique, called the loop-mediated isothermal amplification (LAMP), has been shown to be highly sensitive and specific and is much simpler and faster to perform than conventional NAATs. It requires no intense technical training and expensive equipment. We now propose to evaluate the performance of the LAMP for the diagnosis of TV infection using clinical samples from women attending a Sexual Transmitted Disease (STD) clinic in Uganda. The LAMP assay can potentially be used as a point-of-care (POC) diagnostic tool, also in rural areas in resource-limited settings. Given the high prevalence of TV infection in HIV-endemic areas, TV control could have a substantial beneficial impact by curbing HIV acquisition among women.