Importance of the etiological process in hypersensitivity pneumonitis: about a case caused by goose feathers in a pillow

A 52-year-old woman was investigated for a 6-month history of diffuse interstitial pneumonitis. Clinical and paraclinical findings led to the diagnosis of hypersensitivity pneumonitis (HP). From her history and the visit of her home, two antigenic sources were suspected: a pillow containing goose feathers and mould. Measures revealed low concentrations of fungal microorganisms (<2.10(-3)/m(3) air or g of organic dust for the most frequent species). Precipitins against goose feathers were positive as were precipitins against numerous antigens including various sorts of mould. As recommanded, the patient first left her house bur still slept using he, own pillow then left her house without her pillow and finally went back home but did not sleep with her pillow. Clinical and paraclinical investigations during these periods showed that the HP was caused by goose feathers. In addition to showing a very I rare cause of hypersensitivity pneumonitis, this case report under lines the importance of history, domestic investigations including microbiological,measures and remove tests for identification of causal antigen in case of hypersensitivity pneumonitis.