Pulmonary infiltration with eosinophilia syndrome complicated with non-Hodgkin's lymphoma of B cell lineage

Tissue eosinophilia is often seen in Hodgkin's disease and non-Hodgkin's lymphoma of T cell lineage. It is, however, rare in non-Hodgkin's lymphoma of B cell origin. We report a case of pulmonary infiltration with eosinophilia (PIE) syndrome accompanied with non-Hodgkin's lymphoma of B cell lineage. A 42-year-old man with a long-term history of bronchial asthma consulted the local hospital due to high fever and bilateral cervical lymphadenopathy. He was diagnosed as having non-Hodgkin's lymphoma and was referred to our hospital. Marked blood eosinophilia and infiltrative shadows in both middle lung fields were recognized. After six courses of chemotherapy, including prednisolone, the shadows were ameliorated, although cervical lymphadenopathy did not show any regression, indicating refractory lymphoma. To investigate pulmonary shadows, we performed transbronchial lung biopsy and bronchoalveolar lavage (BAL) at the peak of disease activity before systemic chemotherapy. The eosinophil recruiting and activating factor interleukin (IL)-5 was undetectable in both serum and BAL fluid. Moreover, in the specimen obtained from lung biopsy, tissue eosinophilia was pathologically recognized, but IL-5 was not detected by immunohistochemical staining. These findings indicate that, in this case, any factors other than IL-5 derived from lymphoma cells may be concerned with PIE.