Description Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by gradual destruction and replacement of pulmonary parenchyma with fibrous tissue, which occurs in conjunction with chronic inflammation. It is often considered a prototypical interstitial lung disease and is both the most prevalent and perhaps the most dangerous in that family. Although the disease is uncommon in the general population, its prevalence increases with age and is typically diagnosed around the age of 65. This does not preclude the development of IPF in younger individuals, and the mean survival is 2 to 5 years post-diagnosis regardless of age. Contemporary studies have provided insight into how altered pulmonary parenchyma results in increased susceptibility to opportunistic infections. It has also been demonstrated that pulmonary insults that cause inflammation, such as pneumonia, may accelerate the progression of IPF. Eosinophilic pneumonias are a collection of pulmonary diseases in which eosinophil-mediated inflammation results in respiratory compromise. Early recognition and appropriate intervention are imperative to minimize the risk of residual pulmonary function deficits, a risk that is increased in individuals with separate pulmonary risk factors. While prompt diagnosis and pharmacologic interventions are associated with improved outcomes, patients with IPF remain at risk of deterioration to the point of requiring lung transplantation. Early screening for those at risk continues to be a topic of interest. Despite the prevalence of IPF, its pathogenesis remains poorly understood and few management options are available. In this article, we document a unique case of previously undiagnosed IPF in a young individual that acutely worsened in the setting of acute eosinophilic pneumonia and the involvement of an opportunistic organism,