CRP and infection: Among these, the role of serial CRP measurements in monitoring treatment response has been previously studied.13, 14, 15, 16, 17 Patterns of relative CRP change (i.e., ratio of measurements on day 4 or 5 to those at baseline) has been found to correlate with clinical outcomes.13, 16, 18 However, host responses are heterogeneous, both at presentation and throughout infections,12, 19 due to factors such as the causative pathogens, sources of infection, and individual patient characteristics.