Alveolar proteinosis is an uncommon lung disease presenting in primary or secondary forms, characterised by surfactant derived proteinous material accumulation within the lungs. The most effective treatment remains whole lung lavage under general anaesthesia. We have recently performed whole lung lavage in a 46-year-old patient with alveolar proteinosis who presented with severe dyspnoea and hypoxia. During the left lung lavage, outwards flow was enhanced at random either by manual clapping or by mechanical chest percussion with a vest airway clearance system. The protein and surfactant protein A concentrations in the 13 successive samples of the left lavage solution showed an exponential decline, not different between manual clapping and chest mechanical percussion. The average concentration of surfactant protein was not different between manual clapping and chest percussion. We conclude that in alveolar proteinosis, manual clapping replacement by mechanical chest percussion during whole lung lavage merits further evaluation.