Suzuki A, et al. - In this study, researchers evaluated 144 candidates to examine the pulmonary lesions in Japanese subjects with microscopic polyangiitis (MPA). They noted abnormal chest high-resolution CT (HRCT) findings in 134 cases including ground-glass opacity (50%), reticulation (48%), traction bronchiectasis (42%), honeycombing (31%), and emphysema (22%). They diagnosed interstitial pneumonia (IP) radiologically in 74 cases (51%), 38% of whom had the usual IP (UIP) pattern. In subjects with IP, ground-glass opacity, reticulation, traction bronchiectasis, honeycombing, and interlobular septal thickening were frequently observed. Minor findings like bronchial wall thickening, consolidation, increased attenuation around honeycombing, and traction bronchiectasis were also noticed in candidates with MPA with the UIP or possible UIP pattern.