[Alveolar proteinosis: signs and prognosis using high-resolution computed tomography in 5 patients]

Pulmonary alveolar proteinosis is a rare idiopathic diffuse airspace disease characterized by intraalveolar accumulation of large quantities of lipoproteinaceous material. The clinical presentation and course are variable and the definite diagnosis is made by biopsy or broncho-alveolar lavage (BAL) that also constitutes the unique and empiric treatment. We report the extremely typical HRCT features of the disease found in a series of five patients diagnosed in our institution over a ten-year period. The HRCT signs and their evolution are discussed. A continuous spectrum of findings going from isolated ground glass opacities to lobular consolidation is found, but the most common and invariably present pattern consists of ground glass areas with superimposed smooth septal thickening; these areas have a patchy or geographic distribution--often termed the "crazy-paving" pattern--and are unlike pulmonary findings in any other disease.