| Abstract: | Tuberculosis (TB) probably did not become a problem in sub-Saharan Africa (SSA) until around the 1850s. Poverty, inadequate TB control activities, and the HIV epidemic contribute to SSA having the world's highest TB case notification rate. HIV infection is responsible for a marked increase in TB in 15-45 year olds. In some parts of SSA, up to 70% of TB patients have HIV infection. A healthy immune system controls infection with Mycobacterium tuberculosis and prevents progression to TB but does not rid the body of dormant TB bacilli. HIV infection lowers immunity, therefore increasing susceptibility to TB. 25% of new TB cases each year in SSA are attributable to HIV infection. TB is the leading cause of death in HIV-infected individuals in SSA. The median CD4 count in HIV-infected adult TB patients is 200-250. Many persons in late stage HIV infection with TB are sputum smear negative. HIV-infected persons are more likely to have disseminated and extrapulmonary TB than HIV-negative persons. HIV infection sometimes reduces the skin test response to tuberculin. It is best to avoid anti-TB treatment as a diagnostic test for TB. Clinicians should not treat HIV-infected TB patients with thiacetazone but rather ethambutol. Thiacetazone can induce a severe, and sometimes fatal, skin reaction in HIV-infected persons. Many National TB Programs recommend ethambutol in place of streptomycin due to the problems associated with inadequate sterilization of needles and syringes and the pain associated with streptomycin injections in wasted HIV-infected TB patients. HIV-infected TB patients are more likely to die within 12 months after anti-TB treatment has begun than HIV-negative patients. Active TB may boost HIV replication. The World Health Organization does not yet recommend widespread isoniazid preventive therapy for HIV-positive persons in high TB prevalence countries. |
