An Uncommon Case of Secondary Organizing Pneumonia Due to Influenza Type B

Secondary organizing pneumonia refers to a disease process caused by pulmonary tissue injury. Various insults can cause secondary organizing pneumonia, including multiple types of infections and cancer. The mainstay of diagnosis is a combination of imaging and lung biopsy showing inflammatory changes, specifically plugs with granulated tissue and fibrosis. Clinical suspicion needs to be raised for secondary organizing pneumonia when a patient is requiring increasing amounts of oxygen in the presence of treatment for pneumonia or another underlying lung disease. Here, we present the case of a 65-year-old male who presented with acute hypoxemic respiratory failure in the setting of previously having been tested positive for influenza B. Aggressive steroids with eventual tapering of his O2 requirements led to a successful outcome. While influenza has been reported as a cause of secondary organizing pneumonia after proceeding infection, these cases are usually represented by type A, rather than B.