[Idiopathic chronic eosinophilic pneumonia - a diagnostic challenge]

A 43-year-old woman with clinical signs of a febrile respiratory infection with cough and dyspnea despite several antecedent antibiotic treatments was admitted to hospital because of persistent bilateral pulmonary infiltrates.

In the diagnostic work-up, the most striking laboratory abnormality was an eosinophilia of 31% within the differential blood count. Specimen obtained from bronchoalveolar lavage showed an abnormally high level of eosinophils as well. In the absence of other known causes of an eosinophilic pulmonary disease the diagnosis of idiopathic chronic eosinophilic pneumonia was made. After initiation of corticosteroid medication the abnormal laboratory results, the clinical signs, and the radiologic findings almost completely normalized within 1 week.

If an apparent pneumonia fails to respond to conventional antibiotic treatment, a blood eosinophil count should be obtained. If blood eosinophils are abnormally high, diagnosis of idiopathic acute or chronic eosinophilic pneumonia should be considered and confirmed by demonstrating an excess of eosinophils in bronchoalveolar lavage fluid. Due to prognostic and therapeutic consequences idiopathic acute and chronic eosinophilic pneumonia should be distinguished from one another. A rapid response to glucocorticoid therapy supports the diagnosis. In order to avoid relapses, patients with chronic eosinophilic pneumonia have to complete a 6-month treatment.