Introduction
The human immunodeficiency virus (HIV) and acquired immunodeficiency
syndrome (AIDS) pandemic has become a well-known global health problem
specially in the last decade. Due to the effectiveness of highly active
antiretroviral therapy (HAART), the incidence of new HIV infections has
declined, and the number of AIDS-related deaths in adults and children
worldwide has plateaued (1).
Many of the clinical features of HIV/AIDS can be ascribed to the
profound immune deficiency which develops in infected patients. The
destruction of the immune system by the virus results in opportunistic
infection, as well as an increased risk of autoimmune disease and
malignancy. HIV-related complications are rarely encountered in patients
with preserved immunity (i.e. CD4 T-cell counts greater than 500
cells/mm3). The risk of developing opportunistic infections and
malignancies typical of AIDS increases progressively as CD4 counts fall
below 200 cells/mm3 (2).
However, the respiratory system is still one of the most frequently
affected organ systems in HIV-infected patients, and opportunistic
pulmonary infections (OPIs) remain a major threat (3). The pathogens may
be bacteria, mycobacteria, fungi, or viruses as well.