ESR1 and infection: However, patients with low-virulence PJIs and those without infection had comparable CRP (medians: 12.0 vs. 3.8 mg/L; p = 0.16) and ESR levels (medians: 30.5 vs. 25.0 mm/h; p = 0.15), indicating that these markers are not suitable for the detection of low-virulence PJIs.