Tuberculosis (TB) is the leading cause of death among people living with HIV. In 2015, there were 1.2 million people living with HIV estimated to have fallen ill with TB, and 390,000 people who died from HIV-associated TB. To control TB in high HIV-prevalence settings, it is imperative to coordinate efforts for TB and HIV control. Vanderbilt collaborates with international organizations and performs studies in population-based cohorts to identify ways to reduce the burden of TB among persons living with HIV.
William Wester, M.D., M.P.H. leads a large CDC-PEPFAR-funded initiative in Mozambique entitled, “Avante Zambézia” (“Go forward” Zambézia province) where the Vanderbilt University Medical Center (VUMC)/Friends in Global Health (FGH) team provides technical assistance supporting the scale-up of comprehensive HIV and TB services, including the provision of antiretroviral therapy (ART). Currently beginning year 5 of their initial 5-year cooperative agreement plus beginning year 1 of 5 of a new grant award, the VUMC/FGH team is making great strides in the area of service expansion, as they now support ART services in 112 health facilities across 14 out of 23 districts within Zambézia province; with plans to expand into a 15th district, namely the province’s most populous district (Quelimane) beginning in January 2017. During the recently completed year 4 of the initial grant award (9/30/15-9/20/16), 5,224 new TB patients registered in the program and 92% of eligible HIV/TB co-infected persons initiated ART. During this current funding year, the VU/FGH team plans to specifically focus on improving the timeliness of TB diagnosis via the wide-scale implementation of the Gene Xpert diagnostic test, as well as improve TB infection control via site refurbishment to improve patient flow and air flow/ventilation.
April Pettit, M.D., M.P.H. studies the epidemiology and outcomes of those co-infected with TB and HIV via datasets from large HIV cohort collaborations. Results of an International Epidemiologic Databases to Evaluate AIDS (IeDEA) study examining mortality due to non-AIDS defining events in HIV patients on ART were presented at the International Workshop on HIV Observational Databases (IWHOD) in March 2015. Another IeDEA study led by Pediatric Infectious Diseases Fellow James Carlucci, M.D., looked at TB treatment outcomes in HIV/TB co-infected children in resource limited settings, results were presented at CROI in February 2016. Additionally, Dr. Pettit is involved in clinical studies of TB infection and disease via the Tuberculosis Epidemiologic Studies Consortium and the Tuberculosis Trials Consortium, funded by the Centers for Disease Control and Prevention.
The Caribbean, Central, and South America Network (CCASAnet) for HIV epidemiology, a network of IeDEA and led by Catherine McGowan, M.D., collects and synthesizes data through the Vanderbilt Data Coordinating Center (VDCC). CCASAnet has created a shared repository of HIV patient data that has been merged from 10 sites throughout Latin America. This dataset has allowed high-quality analyses of HIV and TB. The most recent project is evaluating TB treatment intermittency in the continuation phase and associated mortality; preliminary results will be presented at CROI in February 2017.
A newly funded NIH R01 project led by Timothy Sterling, M.D. aims to optimize the treatment of HIV-related TB in a large, genetically diverse cohort in Brazil. Treatment of TB/HIV is complicated by drug-drug interactions and increased drug toxicity risk. The current guidelines recommend a standard 6-month based regimen regardless of HIV status, but recent studies suggest that TB failure and relapse is increased in HIV-infected persons. Pharmacogenomic predictors of TB failure and relapse could help optimize treatment. This project builds on the previously established Regional Prospective Observational Research on TB (RePORT)-Brazil cohort which is enrolling patients from 5 sites in Rio de Janeiro, Salvador and Manaus.
The Vanderbilt Tuberculosis Center (VTC) is a focal point for collaborative efforts in TB research that contribute to a reduction in the burden of TB/HIV globally, including Tennessee and Nashville. The VTC also provides technical assistance to local and global service programs engaged in TB control including the Metro Nashville Public Health Department and the Tennessee Department of Health.