PR3-ANCA-positive Pulmonary Cryptococcosis

A 68-year-old man had multiple left pulmonary nodules with serum positivity for proteinase 3 anti-neutrophil cytoplasmic autoantibody (PR3-ANCA) and negativity for cryptococcal antigen (Picture 1). We initially regarded him as having granulomatosis with polyangiitis (GPA). He subsequently underwent a video-assisted surgical lung biopsy for the diagnosis (Picture 1, arrowheads). Hematoxylin and eosin staining of the specimen showed necrotic tissue in the nodule and no vasculitis (Picture 2a). Grocott staining of the nodule revealed cryptoccocal organisms (Picture 2b). Therefore, he was diagnosed with pulmonary cryptococcosis. The PR3-ANCA levels can increase in cases of infection, nonvasculitic connective tissue disease, and other conditions (1). We herein report the first case of PR3-ANCA-positive pulmonary cryptococcosis in the English literature. Not only GPA but also other diseases such as pulmonary cryptococcosis should be considered in cases with PR3-ANCA-positive pulmonary nodules.