ATS issues report on emerging issues in HIV-associated pulmonary disease

The report appears in the March 1, 2011, issue of the Proceedings of the American Thoracic Society.

Since it first came to the public eye in the early 1980s, HIV infection has caused an estimated 25 million deaths worldwide. Patients whose immune systems are weakened by HIV infection historically have been prone to acute lung diseases and infections, most notably tuberculosis (TB) and pneumonia. However, with the introduction of combination antiretroviral therapy (ART) there has been a shift toward more chronic lung diseases among HIV-infected patients in countries where ART is widely available.

Because of the importance of HIV-associated pulmonary diseases and the rapidly evolving knowledge about their development and epidemiology, the American Thoracic Society convened a workshop to discuss current and emerging trends and issued a report based on those findings.

"In the early, pre-ART years of the HIV epidemic, pulmonary infections such as Pneumocystis pneumonia (PCP), TB and bacterial pneumonia were the most frequent pulmonary complications among HIV patients," said Alison Morris, MD, associate professor of medicine and immunology, Division of Pulmonary, Allergy and Critical Care Medicine at the University of Pittsburgh School of Medicine. "Currently, infectious diseases are less common, although still prevalent, and diseases such as emphysema, pulmonary arterial hypertension (PAH) and lung cancer appear to be increasing. New syndromes associated with ART have also become important.

"Despite the importance of pulmonary diseases in HIV and the rapidly evolving understanding of their pathogenesis and epidemiology, few avenues exist for the discussion and dissemination of new clinical and basic insights," she said. "This report summarizes the findings of the workshop members, and offers insight into the evolving landscape of HIV and its treatment."

While shifts in disease conditions have occurred in areas of the world where ART is available and accessible, in areas where access to ART is limited HIV-infected patients still suffer from opportunistic pulmonary infections such as TB in low-income and middle-income countries where TB is endemic, and from PCP and bacterial pneumonia in the U.S. and Western Europe, she added. As a result, clinicians have been faced with treating a wider number of HIV-associated diseases.

"Pulmonary diseases are major causes of morbidity and death in people with HIV infection," she said. "Millions of people with HIV and AIDS throughout the world are at risk of opportunistic pneumonias. However, the availability of combination antiretroviral therapy has turned HIV into a chronic disease, and noninfectious lung diseases are also emerging as important causes of illness. Understanding the differences among these populations can aid clinicians in identifying and treating HIV-associated pulmonary conditions."

Recent research has also aided clinicians in developing a better understanding of HIV, which may in turn lead to new treatments, Dr. Morris added.

"Clinical understanding of the pulmonary immune response in HIV-infected people has greatly improved over the past several years, and now offers new possibilities for treatment and prevention of pulmonary disease," she said.

Co-chairs of the workshop committee included Kristina Crothers, MD, of the University of Washington, James M. Beck, MD, of the University of Michigan, and Laurence Huang, MD, MAS, of the University of California, San Francisco.

"The epidemiology, manifestations and outcomes of pulmonary disease vary depending on availability of ART, and noninfectious conditions may become more common in the current era of the AIDS epidemic, particularly in those with access to ART," Dr. Morris said. "We expect that pulmonary disease will continue to be an important co-morbidity in persons with HIV and continued research is needed to track these complications and explore new treatment modalities."

Provided by American Thoracic Society