Tigecycline-induced Drug Fever and Leukemoid Reaction

In this study, we describe a patient in whom tigecycline-induced drug fever and leukemoid reaction (LR) after 3 weeks of therapy for pneumonia.A 62-year-old man developed aspiration pneumonia on February 1, 2015. He had received multiple antibiotics at another hospital, but did not respond well. Disease rapidly progressed, and he was referred to our department on February 14. We adjusted the antibiotic therapy to tigecycline + vancomycin, and added voriconazole to empiric antifungal therapy. Pneumonia largely improved, and we discontinued vancomycin and voriconazole on February 28. With tigecycline monotherapy, his clinical status remained stable.On March 7, he developed high fever and LR (white blood cell count: 38.25 × 10(9)/L). Erythrocyte sedimentation rate and C-reactive protein were elevated, and CD8+ T cells had been abnormally activated. After a careful physical examination and laboratory investigation, we confirmed that primary infection did not progress and no other cause was evident. So we figured fever and LR might be induced by tigecycline. After discontinuing tigecycline and adding low-dose steroid, fever and LR totally resolved in 3 days, which further confirmed our diagnosis.According to this case and literature review, drug-induced hypersensitivity should be considered in the differential diagnosis of fever and LR when the therapeutic duration of tetracycline approximates 3 weeks. Monitoring T-cell subsets may facilitate early diagnosis. When necessary, we should discontinue the suspected drug to confirm diagnosis.