Receiver operating characteristic curves of using PCT, CRP, WBC and N% to predict sepsis of patients with type 2 diabetes mellitus. PCT exhibited the largest AUC compared with the other three indexes therefore, PCT had better diagnostic efficacy for sepsis compared with CRP, WBC and N%. PCT, procalcitonin; CRP, C-reactive protein; N%, neutrophil percent; WBC, white blood cells; AUC, area under the curve.