UIP in chronic nitrofurantoin toxicity, high magnification
UIP in chronic nitrofurantoin toxicity, high magnification

UIP in chronic nitrofurantoin toxicity: At higher magnification, advanced remodeling of the parenchyma is evident, with little visible preserved lung (upper right corner of image). Note the "fibroblast foci" (FF), characteristic (but not diagnostic) features of the UIP pattern. Most of the changes in this photograph correspond to "microscopic honeycombing." Hematoxylin and eosin stain 200X original magnification.