When grouping infected patients by infection subgroups, patients in the definitive infection group demonstrated significantly higher median serum CRP levels (24.3 mg/l), when compared to probable, possible infection groups and PJI unlikely group (8 mg/l, 8.3 mg/l, 3.6 mg/l, respectively, p < 0.05) (Fig. 2). The gene discussed is CRP; the disease is infection.