CRP and infection: Outpatient parenteral antimicrobial therapy (OPAT) is often used as an effective, less costly alternative to inpatient treatment of severe infections.1 To ensure OPAT safety, both the Infectious Disease Society of America (IDSA) and UK Good Practice Recommendations endorse serial monitoring of complete blood cell counts, renal panels, and liver function tests.1,2 However, these guidelines lack recommendations for monitoring of inflammatory markers for efficacy [e.g. erythrocyte sedimentation rate (ESR), C-reactive protein (CRP)].