We report a case of a patient admitted to hospital for respiratory distress caused by an acute alveolitis due to exposure to goose feathers in a duvet. Several months after the acute episode a series of examinations, including a broncho-alveolar lavage, were performed before and after a challenge test of exposure to the suspected duvet. We noted a febrile reaction, an increase of the alveolar-arterial oxygen gradient, a rise in neutrophils both in the blood and broncho-alveolar lavage liquid. In the absence of specific demonstrable antibodies, this surge of neutrophils in the alveolar walls does not seem to be due to an immune complex reaction, but is more likely to be a non-immunological phenomenon.