Mycobacterium tuberculosis and HIV Coinfection Brings Fire and Fury to Macrophages

Clinical studies have provided compelling evidence that people coinfected with human immunodeficiency virus (HIV) and Mycobacterium tuberculosis have a 20-30-fold higher risk of developing active tuberculosis as compared to individuals with M. tuberculosis monoinfection Considering the critical role of T cells in preventing tuberculosis dissemination and the reduction of CD4 + T cells in HIV-positive patients, it was anticipated that the number of circulating CD4 + T cells should be directly linked to prevention or reactivation of latent M. tuberculosis infection. However, the risk of developing active tuberculosis is significantly increased during the early phase of HIV infection [2] or after antiretroviral therapy [3], conditions in which CD4 + T-cell counts may be within the normal range. These data indicate that the decline in the number of CD4 + T cells in HIV-infected individuals may not be solely responsible for the progression from latent M. tuberculosis infection to active tuberculosis