Management of Rising WBC Count in a Patient on Vancomycin and Cefepime

Rationale for Dose Escalation

The dramatic increase in WBC count (from 15 to 32) suggests inadequate control of infection with the current antibiotic regimen, requiring prompt optimization of antimicrobial therapy 1
For patients at high risk of mortality or with severe infections, higher doses of cefepime (2g every 8 hours) are recommended in clinical practice guidelines, as suggested by the Infectious Diseases Society of America 1, 2

The current vancomycin dose of 1 gram daily may also be suboptimal for severe infections, and the Infectious Diseases Society of America recommends considering monitoring vancomycin trough levels and potentially increasing frequency to maintain therapeutic concentrations 1
For serious infections, vancomycin dosing should target trough levels of 15-20 mg/mL, according to the Infectious Diseases Society of America guidelines 1
Consider monitoring vancomycin trough levels and potentially increasing frequency to maintain therapeutic concentrations, especially if MRSA is a concern, as recommended by the Infectious Diseases Society of America 1, 2

Consider obtaining cultures (if not already done) to guide targeted therapy, as recommended by the American Heart Association 3
Monitor clinical response including temperature, hemodynamic parameters, and subsequent WBC counts, as suggested by the American Heart Association 3

Delaying dose optimization when clinical deterioration is evident (rising WBC count), which is a critical mistake according to the Infectious Diseases Society of America 1
Not reassessing the need for continued combination therapy once culture and susceptibility results are available, as recommended by the American Heart Association 3