Vancomycin-Induced Leukopenia and Neutropenia: Time Will Tell.

Purpose: Neutropenia is an uncommon adverse effect associated with prolonged vancomycin therapy. Methods: This was a case report on a 62-year-old African American male with hypertension, paranoid schizophrenia, and a history of polysubstance abuse developed foot osteomyelitis. The patient was initially maintained on intravenous Vancomycin & Ceftriaxone for ~3 weeks but adjusted to Daptomycin & Ceftriaxone while in hospital due to neutropenia. Patient's neutropenia quickly resolved once discontinuation of Vancomycin occurred. Results: Vancomycin is a potential cause of drug induced leukopenia and neutropenia. Monitoring of leukocytes and neutrophils is warranted in patients receiving long term intravenous Vancomycin therapy. Conclusion: Vancomycin is a bactericidal glycopeptide antibiotic with activity against gram-positive organisms such as Staphylococci. Well-known adverse drug events include nephrotoxicity and ototoxicity. Vancomycin-induced neutropenia on the other hand is less common and reported at lower rates. It is defined as an ANC less than 1000 µL in patients maintained on Vancomycin infusions. According to Black et al, neutropenia is more likely associated with prolonged therapy; generally occurring at least 20 days after initiation.