GM-CSF-induced acute eosinophilic pneumonia

Summary. There is increasing evidence that haemopoietic growth factors are effective in reversal of neutropenia associated with large granular lymphocytes (LGLs) proliferation. A 19-year-old woman with CD3⁺/TCRγδ⁺, CD4⁻, CD8⁻ LGL proliferation and severe neutropenia repeatedly developed blood eosinophilia, fever and dyspnoea after administration of GM-CSF. Acute eosinophilic pneumonia with a lobar lung infiltrate pleural effusion, and marked bronchoalveolar lavage fluid eosinophilia was diagnosed. Treatment with corticosteroids and discontinuation of GM-CSF lead to rapid improvement. In addition, haematological analysis revealed that H*1 Technicon, a widely-used automated cell counter, may misinterpret eosinophils erroneously as neutrophils, therefore examination of blood smears to prevent eosinophil-medlated toxicity during GM-CSF treatment is recommended.