Methods: A single center, retrospective cohort study was conducted to identify patients ≥18 years of age on daptomycin and vancomycin for ≥ 5 days from July 1, 2013 to June 30, 2014. Patients were excluded if daptomycin was administered prior to admission, if eosinophilia was present at baseline, or if they had a history of asthma, eczema, parasitic disease, systemic lupus erythematosus, rheumatoid arthritis, lymphoma, or solid tumors. The primary endpoint is the incidence of peripheral eosinophilia. Secondary endpoints include: degree of eosinophilia (mild, moderate, severe), average dose of daptomycin when eosinophilia occurred, time to onset of eosinophilia, and simultaneous B-lactam use.
Results: Charts were reviewed for 333 patients. In this cohort, 131 met inclusion criteria including 94 patients in the vancomycin group and 37 patients in the daptomycin group. Patients in the daptomycin group were more likely to develop peripheral eosinophilia compared to patients on vancomycin 2.96 (95% CI 1.32-6.63). Amongst the secondary endpoints, patients on higher doses of daptomycin were more likely to develop of eosinophilia (7.01mg/kg vs. 6.2mg/kg, p= 0.031). All other secondary endpoints were not statistically significant.
Conclusion: Mild peripheral eosinophilia does appear to occur with daptomycin use and higher daptomycin doses may be associated with the development of eosinophilia. Currently, the clinical implications of peripheral eosinophilia are unknown. However, this study demonstrates that eosinophil count in patients on daptomycin may need to be monitored more closely.
M. Rasnake, None
B. Sammons, None
J. Mendez, None
R. E. Heidel, None