Nathaniel T. Marchetti, DO has special expertise in chronic obstructive lung disease (COPD), interstitial lung disease, critical care, and lung transplant. He has co-authored over 65 publications with a focus on COPD, and has conducted a vast amount of clinical research on a variety of conditions that lead to advanced lung disease. Dr. Marchetti is a Philadelphia magazine Top Doctor for Pulmonary Disease and a peer-selected The Best Doctors in America®, Pulmonary Medicine.