CT scan patterns of pulmonary alveolar proteinosis in children

Background. To study computed tomographic (CT) findings in children with pu lmonary alveolar proteinosis (PAP) more extensively. Objective. To describe the CT features at the time of diagnosis and after t herapeutic broncho-alveolar lavage (BAL). Materials and methods. We retrospectively reviewed the CT scans of five chi ldren (aged 3 months to 4 years) examined because of incidental bronchitis (n = 1), disease in a sibling (n = 1) and relapsing fever, cough and dyspno ea (n = 3). Each patient had an initial CT scan. Two asymptomatic cases wer e not treated but were followed up by plain chest films. The other three ha d BAL and follow-up CT. Results. Initial CT in all cases showed a diffuse reticulomicronodular patt ern associated in three cases with posterior bilateral alveolar infiltrates . CT in the two asymptomatic patients remained unchanged or slightly improv ed without BAL. After BAL, a variable decrease of lung infiltrates was obse rved. onclusions. Correlation between the extent of alveolar consolidation and se verity of disease was found. Anatomical and pathological considerations all ow us to consider that the classical reticulomicronodular pattern is not du e to an interstitial infiltration but to alveoli filled with the abnormal m aterial characteristic of PAP.