The syndemic of human immunodeficiency virus (HIV)/tuberculosis (TB) co-infection has grown as a result of the considerable sociogeographic overlaps between the two epidemics. The situation is particularly worrisome in countries with high or intermediate TB burden against the background of a variable HIV epidemic state. Early diagnosis of TB disease in an HIV-infected person is paramount but suffers from lack of sensitive and specific diagnostic tools. Enhanced symptom screening is currently advocated, and the wide application of affordable molecular diagnostics is urgently needed. Treatment of TB/HIV co-infection involves the concurrent use of standard antiretrovirals and antimycobacterials during which harmful drug interaction may occur. The pharmacokinetic interaction between rifamycin and antiretrovirals is a case in point, requiring dosage adjustment and preferential use of rifabutin, if available. Early initiation of antiretroviral therapy is indicated, preferably at 2 weeks after starting TB treatment for patients with a CD4 of <50 cells/μL. Development of TB-immune reconstitution inflammatory syndrome (TB-IRIS) is however more frequent with early antiretroviral therapy. The diagnosis of TB-IRIS is another clinical challenge, and cautious use of corticosteroids is suggested to improve clinical outcome. As a preventive measure against active TB disease, the screening for latent TB infection should be widely practiced, followed by at least 6-9 months of isoniazid treatment. To date tuberculin skin test remains the only diagnostic tool in high TB burden countries. The role of alternative tests, for example, interferon-γ release assay, would need to be better defined for clinical application.
Keywords: antiretroviral therapy; immune reconstitution inflammatory syndrome; latent tuberculosis; tuberculosis.
© 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.