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 inter stitial pneumonitis. Clinical and paraclinical findings led to the diagnosi s of hypersensitivity pneumonitis (HP). From her history and the visit of h er home, two antigenic sources were suspected: a pillow containing goose fe athers and mould. Measures revealed low concentrations of fungal microorgan isms (<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 aga inst numerous antigens including various sorts of mould. As recommanded, th e patient first left her house bur still slept using he, own pillow then le ft her house without her pillow and finally went back home but did not slee p with her pillow. Clinical and paraclinical investigations during these pe riods showed that the HP was caused by goose feathers. In addition to showi ng a very I rare cause of hypersensitivity pneumonitis, this case report un der lines the importance of history, domestic investigations including micr obiological,measures and remove tests for identification of causal antigen in case of hypersensitivity pneumonitis.