Therapeutic lung lavages in children and adults

Background: Pulmonary alveolar proteinosis ( PAP) is a rare
disease, characterized by excessive intra-alveolar accumulation of
surfactant lipids and proteins. Therapeutic whole lung lavages are
currently the principle therapeutic option in adults. Not much is
known on the kinetics of the wash out process, especially in
children. Methods: In 4 pediatric and 6 adult PAP patients 45
therapeutic half lung lavages were investigated retrospectively.
Total protein, protein concentration and, in one child with a
surfactant protein C mutation, aberrant pro-SP-C protein, were
determined during wash out. Results: The removal of protein from
the lungs followed an exponential decline and averaged for adult
patients 2 - 20 g and < 0.5 to 6 g for pediatric patients. The
average protein concentration of consecutive portions was the same
in all patient groups, however was elevated in pediatric patients
when expressed per body weight. The amount of an aberrant pro-SP-C
protein, which was present in one patient with a SP-C mutation,
constantly decreased with ongoing lavage. Measuring the optical
density of the lavage fluid obtained allowed to monitor the wash
out process during the lavages at the bedside and to determine the
termination of the lavage procedure at normal protein
concentration. Conclusion: Following therapeutic half lung lavages
by biochemical variables may help to estimate the degree of
alveolar filling with proteinaceous material and to improve the
efficiency of the wash out, especially in children.