Clinical Features and Radiological Findings of Adenovirus Pneumonia Associated with Progression to Acute Respiratory Distress Syndrome: A Single Center Study in 19 Adult Patients

Cha, Min Jae; Chung, Myung Jin; Lee, Kyung Soo; Kim, Tae Jung; Kim, Tae Sung; Chong, Semin; Han, Jungho

On CT, the patterns of parenchymal abnormalities were subdivided into areas of ground-glass opacity (GGO), consolidation, and micronodules (< 5 mm in diameter). GGO was defined as an area of hazy increased lung opacity, within which margins of pulmonary vessels were indistinct. Consolidation was defined as a homogeneous increase in pulmonary parenchymal opacity that obscured the margins of vessels and airway walls (18) . The presence of interlobular septal thickening or pleural effusion was also recorded, and the laterality (unilateral vs. bilateral) of the lesions was evaluated. Septal thickening was defined as abnormal widening of an interlobular septum or septa (18) . In terms of anatomic location, the distribution of parenchymal abnormalities was classified as central, peripheral, or mixed in the axial plane and upper, lower, or random in the longitudinal plane. The outer third of the lung was defined as peripheral, and the inner twothirds of the lung were defined as central. The lesions were regarded as distributed in the upper lung zone when they were located above the hilum, in the lower lung zone when they were located below the hilum, or random when the distribution could not be determined. For the acquisition of CT scores, the lung was also divided into upper (above the carina), middle (below the carina and up to the inferior pulmonary vein), and lower (below the inferior pulmonary vein) zones. The involvement of pneumonia within each lung zone was evaluated by scoring each zone from 0 (normal) to 4, with 4 corresponding to nearly total involvement of the lung parenchyma. Total CT scores ranged from 0 to 24 when combined for all six zones (17, 19) .