Acute Interstitial Pneumonia

Acute interstitial pneumonia (AIP - also known as Hamman-Rich syndrome) is an acute, rapidly progressive idiopathic pulmonary disease that often leads to fulminant respiratory failure and acute respiratory distress syndrome (ARDS). It can be distinguished clinically from other types of interstitial pneumonia by the rapid onset of respiratory failure in a patient without preexisting lung disease. Louis Hamman and Arnold Rich first described it in 1935 as a fulminating diffuse interstitial fibrosis of the lungs. In 1986, Katzenstein introduced the term AIP differentiating it from the group of chronic interstitial pneumonia. The American Thoracic Society (ATS) and European Respiratory Society (ERS) classify AIP under major idiopathic interstitial pneumonia, compared to other rare or unclassified idiopathic interstitial pneumonia.