INS and type 2 diabetes mellitus: First, in order to demonstrate the effect of T2DM on immunity of patients with severe sepsis, this study selected infection-free T2DM patients that had a similar history of diabetes and similar medication as those patients with both T2DM and severe sepsis, however, the effect of some confounding factors, such as metabolic control, diabetes-related complications, obesity, and insulin or other medications, on the prognosis of severe sepsis with diabetes can not be ruled out [35].