Primary pulmonary alveolar proteinosis: computed tomography features at diagnosis

Pediatr Radiol. 2014 Jul;44(7):795-802. doi: 10.1007/s00247-014-2888-1. Epub 2014 Mar 6.


Background: Pulmonary alveolar proteinosis (PAP) is characterized by an abnormal accumulation of periodic acid-schiff-positive lipoproteinaceous material in the alveoli. Early diagnosis allows setting up of therapeutic lung lavages, which reduces the need for oxygen supplementation and weight gain.

Objective: To provide a description of radiological features by CT at the onset of primary PAP in children.

Materials and methods: The clinical and radiological data of 24 patients, including 16 boys and 8 girls (median age: 12 months), diagnosed with a primary form of PAP between April 1992 and May 2012 in a tertiary referral hospital, were retrospectively reviewed. CT images were examined for the presence of alveolar and interstitial elementary lesions. Correlation between clinical and radiological findings was assessed.

Results: The types of elementary lesions detected were: ground-glass opacities (n = 24), intralobular lines (n = 24), thickened interlobular septa (n = 22), thickened fissures (n = 21), airspace consolidation (n = 16), hyperinflation (n = 16), cystic lesions (n = 2) and micronodules (n = 1). A crazy-paving pattern was found in 92% of cases. Consolidation and hyperinflation were especially detected in younger children (median age, 8 months, P < 0.01). A density dependent gradient was found. The distribution of the lesions was symmetrical. There was no correlation between radiological and clinical data of severity of the disease.

Conclusion: CT findings are suggestive of diagnosis of PAP in immunocompetent children with chronic respiratory failure.

MeSH terms

  • Child
  • Child, Preschool
  • Female
  • Humans
  • Infant
  • Lung / diagnostic imaging
  • Male
  • Pulmonary Alveolar Proteinosis / diagnostic imaging*
  • Retrospective Studies
  • Tomography, X-Ray Computed*