[A case of acute eosinophilic pneumonia: bronchoalveolar lavage findings before and after steroid treatment].

An 18-year-old woman presented with coughing, fever, progressive dyspnea, and diffuse infiltrates on the chest X-ray film. Analysis of bronchoalveolar lavage fluid showed 73% eosinophils. Acute eosinophilic pneumonia was diagnosed. Methylprenisolone, 1 g per day was given for three days and her condition improved dramatically. No relapse was observed. Analysis of bronchoalveolar lavage fluid also showed lymphocytosis, abnormally high concentrations of ECP, GM-CSF, IL-5 and sICAM-1, and hypersegmentation of eosinophil nuclei. After steroid treatment almost all these findings returned to normal; only lymphocytosis remained. Precipitating antibodies against four kinds of fungi, including Trichoderma viridae, were noted in the serum, but the environmental provocation test was negative and those fungi were not detected in the environmental culture growth. Comparison of bronchoalveolar lavage findings obtained before and after steroid treatment can provide information on the mechanism of eosinophil accumulation in the lung. This case also draws attention to the relationship between acute and chronic eosinophilic pneumonia.