Noninfectious and Nonneoplastic Conditions Associated with Human Immunodeficiency Virus Infection

The goal of this review is to describe evolving epidemiology of noninfectious, nonneoplastic pulmonary complications of HIV infection, including HIV-associated pulmonary arterial hypertension (HIV-PAH) and interstitial lung disease (ILD). The development of antiretroviral therapy has rendered HIV a chronic illness in treated patients, and the landscape of HIV-associated medical conditions continues to evolve. Although there has been a shift away from AIDS-defining infectious diseases and malignancies, HIV-PAH continues to affect survival adversely when compared with HIV-infected patients without PAH. Studies of pre- and post-highly active antiretroviral therapy (HAART) era show that the prevalence of HIV-PAH remains high and unchanged. The increased prevalence of PAH among HIV-infected individuals has led to several complementary theories about potential mechanisms underlying this disease. Unique mechanisms of HIV-PAH focus on direct effects of viral proteins; alterations in cellular immunologic/inflammatory reactions to the virus; additive effects of cocaine, heroin, and other drugs of abuse; and potentially toxic aspects of antiretroviral and associated therapies. PAH-specific therapy with HAART is likely beneficial in the treatment of HIV-PAH patients. The prevalence of ILD in HIV-infected individuals is also significantly higher than that in the general population. Lymphoid interstitial pneumonitis (LIP) and nonspecific interstitial pneumonia (NSIP) have been reported in both HIV-infected children and adults, and NSIP is more common than LIP in HIV-infected patients. At present, there is no consensus on the pathogenesis of LIP and NSIP in HIV. Finally, we briefly review the literature on venous thromboembolic disease in HIV-infected individuals.