Rapid diagnosis of acute eosinophilic pneumonia (AEP) in a patient with respiratory failure using bronchoalveolar lavage (BAL) with calcofluor white (CW) staining.

A diagnosis of exclusion, acute eosinophilic pneumonia (AEP) is an acute febrile illness with respiratory impairment, diffuse pulmonary infiltrates, and bronchoalveolar lavage (BAL) fluid eosinophilia. Whether pulmonary eosinophilia in AEP is primary or secondary remains undetermined. We report here a 22-year-old auto mechanic with severe AEP and acute respiratory failure who required intubation and ventilatory support. The patient's bronchoalveolar lavage (BAL) fluid was analyzed using cultures, cytology, Wright/Giemsa, Gram, Gomori-methenamine-silver (GMS), and calcofluor white (CW) stains (1). Despite extensive evaluation, no infectious etiology was found. CW staining helped us rapidly to exclude Pneumocystis carinii or fungal infection and to focus attention toward the diagnosis of AEP. Transbronchial biopsy was unnecessary and supportive therapy without systemic glucocorticoids was followed by recovery within a few weeks. In this case, bronchoalveolar lavage with CW staining was of great assistance in the rapid diagnosis and initial management of AEP. Our literature review found no prior article using CW staining for evaluation of AEP.