Moxifloxacin Plus Metronidazole Versus Piperacillin/Tazobactam for the Treatment of Patients With Intra-abdominal Abscesses

Inclusion Criteria: * Patients who attained full age (18 years) with intra-abdominal abscesses documented by: A) Laparotomy revealing intra-abdominal abscess or macroscopic gastrointestinal perforation OR B) Suspected intra-abdominal abscess and scheduled for operation with at least three of the following criteria: * fever, * leucocytosis, * symptoms referable to the abdominal cavity (nausea, pain), * tenderness with or without rebound / abdominal wall rigidity, * radiological evidence for abscess or gastrointestinal perforation. Exclusion Criteria: * Patients with the following: * indwelling peritoneal catheter, * presumed spontaneous bacterial peritonits, * peripancreatic sepsis or infection secondary to pancreatitis, * peptic or traumatic perforation of gastrointestinal tract of \< 24 h duration, * traumatic perforation of the small or large bowel of \< 12h duration, * transmural necrosis of the intestine due to acute embolic, thrombotic or obstructive occlusions, * acute cholecystitis, * appendicitis without perforation or abscess, * required open abdomen techniques for management, * gynaecological infection, * known hypersensivity to any of the study drugs, * lifethreatening disease with life expectancy of less than 48 hours, * neutropenia with neutrophil count \< 1000 cells/µl, * receiving chronic treatment with imunosuppressant therapy, * HIV-seropositives with CD4 count \< 200 cells/µl, * end stage hepatic cirrhosis CHILD PUGH C, * central or peripheral neuropathy, * bradycardia, * symptomatic dysrhythmia in medical history, * syndromes of QTc prolongation or use of concomittant medicaments reported to increase QT interval, * disorder of the electrolyte balance, * previous history of tendinopathy with quinolones, * previously enrolled in the trial or use of any investigational drug within the previous 30 days