The four variables; serum albumin (g/L) (P = 0.001), CRP (mg/L) (P = 0.020), WCC ( × 103 mcL) (P = 0.025) and respiratory rate (resps/min), (P = 0.003) were identified by univariate and multivariate analysis as being significant predictors of all-cause mortality in patients with CDI (Additional file 1). The gene discussed is CRP; the disease is clostridium difficile infection.