Probiotics significantly reduced postoperative infections (risk ratio = 0.49, 95% CI: 0.26-0.92, <i>p</i> = 0.027) and C-reactive protein elevation (risk ratio = 0.42, 95% CI: 0.26-0.68, <i>p</i> < 0.001) and increased <i>Bifidobacterium</i> abundance (standardized mean difference = 0.84, 95% CI: 0.51-1.17, <i>p</i> < 0.001). The gene discussed is CRP; the disease is infection.