Pulmonary alveolar proteinosis is a rare syndrome characterized by intra-alveolar accumulation of
surfactant components and cellular debris, with minimal interstitial inflammation or fibrosis. The
condition has a variable clinical course, from spontaneous resolution to respiratory failure and death
due to disease progression or superimposed infections. The standard of care for alveolor proteinosis
therapy is represented by whole lung lavage. Important discoveries have been made in the last decade
with respect to disease pathogenesis and therapy of both congenital and acquired forms of the disease.
Granulocyte-macrophage colony-stimulating factor (GM-CSF) pathway has been shown to be
involved in the disease pathogenesis of both acquired and congenital disease. Furthermore, anti-GMCSF
blocking autoantibodies have been found in the serum and bronchoalveolar lavage fluid and
seem to interfere with the surfactant clearance by alveolar macrophages in many acquired cases. In
the congenital form, the most common defects identified to date are several mutations of the genes
encoding GM-CSF receptor subunits or surfactant proteins. Using GM-CSF as a therapeutic tool has
also been shown to be effective in at least half of the acquired cases treated, while the importance of
quantitative determination of anti-GM-CSF antibodies before and during the course of the therapy,
as well as the autoantibody titer–GM-CSF dose relationship are to be elucidated. The congenital
form of the disease does not respond to therapy with GM-CSF, consistent with the known primary
defects and differences in disease pathogenesis. Chronic Respiratory Disease 2006; 3: 149–159
Key words: autoantibodies, bronchoalveolar lavage, granulocyte-macrophage colony-stimulating
factor (GM-CSF), pulmonary alveolar proteinosis, pulmonary surfactant