Pediatric diffuse lung disease: Diagnosis and classification using high-resolution CT

OBJECTIVE. Our purpose was to categorize high-resolution CT findings in chi ldren with diffuse lung disease and to evaluate the accuracy of diagnoses m ade using CT. MATERIALS AND METHODS. The chest radiographs and high-resolution CT scans o f 20 children (1-16 years old; median, 9 years old) with biopsy-proven chro nic diffuse lung diseases were reviewed separately by two independent chest radiologists. Thirteen types of diffuse lung disease were included in the study. Radiographic and CT features were noted, and three choices of diagno sis were recorded, with the confidence level. RESULTS. Diagnoses were made with a high degree of confidence (definite or probable) in 25 of 40 interpretations of CT scans, compared with only five of 40 interpretations of chest radiographs (p < .001). Fourteen (56%) of th e 25 confident first-choice diagnoses on CT scans were correct, compared wi th two (40%) of the five interpretations on chest radiographs. Diseases wer e classified as belonging to one of five distinct groups on the basis of do minant CT features. Airway disease (n = 5) (bronchiolitis obliterans or bro nchocentric granulomatosis) showed geographic hyperlucency on CT. Septal di sease (n = 4) (lymphangiomatosis, hemangiomatosis, or microlithiasis) showe d septal thickening. Infiltrative lung disease (n = 7) (desquamative inters titial pneumonitis, hypersensitivity pneumonitis, or lymphoid interstitial pneumonitis) showed ground-glass opacity. Air-space disease (n = 3) (aspira tion, vasculitis, or bronchiolitis obliterans organizing pneumonia) showed lung consolidation. Langerhans' histiocytosis (n = 1) showed cysts and nodu les. Surprisingly little overlap was seen among these groups. CONCLUSION. CT increases the level of diagnostic confidence for pediatric i nfiltrative lung disease, improves diagnostic accuracy, and provides a usef ul classification system.