A female presents with history of progressive breathlessness. Histology shows heterogenous patchy fibrosis with several fibroblastic foci. The most likely diagnosis is:: (A) Cryptogenic Organizing Pneumonia, (B) Non Specific Interstitial pneumonia, (C) Usual Interstitial Pneumonia, (D) Desquamative Interstitial Pneumonia
Answer is C. Histologic hallmark of UIP is a heterogeneous appearance at low magnification with alternating areas of normal lung, interstitial inflammation, foci of proliferating fibroblasts, dense collagen fibrosis and honeycomb changes. Ref: Harrison's Principles of Internal Medicine, 16th Edition, Page 1557.