Penetration of Ertapenem Into Bone

Inclusion Criteria: * Age \> 18 * Diabetes Mellitus or Peripheral Vascular Disease * Undergoing bellow knee amputation with or without gangrene * Patients without clinical signs of acute infection * Creatinine Clearence more than 60 cc/ min Exclusion Criteria: * Known hypersensitivity to any component of ertapenem or to other drugs in the same class. * Patients who have demonstrated anaphylactic reactions to beta-lactams. * CNS disorders (e.g., brain lesions or history of seizures). * Patient treated with other antibiotics at least 72 hours. * Pregnant women, nursing women, or fertile women not practicing adequate methods of contraception. * Patient or legal representative of the patient is unable to provide written informed consent for any reason. * Patient has a history of any illness that, in the opinion of the investigator, might confound the results of the study or pose additional risk in administering the study drug to the patient. * Neutropenia * Renal failure * Hepatic Insufficiency: \> x 2 upper limit. * A need for any additional concomitant systemic antibacterial agent. * Life expectancy less than 6 month * Patient is undergoing immunosuppressive therapy, including use of high dose corticosteroids (e.g.,20 mg or more prednisone or equivalent per day) * Patient is in a situation or has a condition which, in the investigator's opinion, may interfere with optimal participation in the study. * Participation in an another clinical trial.