ALB and clostridium difficile infection: Currently, two American guidelines define patients with severe CDI (for whom the initial treatment should be vancomycin, a drug thought to lower the risk of complications) as those with a leucocytosis (WBC >15×109/L) and/or a creatinine >1.5 times the baseline [80], and with WBC >15×109/L plus a serum albumin <3 g/dl or abdominal tenderness [75].