Background and objective: The clinical course and death rate in acute necrotizing pancreatitis (ANP) are largely determined by septic complications as part of bacterial invasion of the necrotic tissues. It remains unclear whether antibiotic prophylaxis reduces bacterial invasion of the necroses or septic complications. It was, therefore, the aim of this study to evaluate the effect of prophylactic administration of antibiotics to patients with ANP.
Patients and methods: In a prospective randomized study 13 patients with ANP and sterile necroses (quantified by contrast-enhanced computed tomography) were given twice daily 200 mg ofloxacin and twice daily 500 mg metronidazole intravenously. The results were compared to those in a control group of patients with ANP (n = 13) who had not initially received antibiotics. In both patient groups fine-needle biopsies of the necrotic areas were performed on days 1, 3, 5, 7 and 10. If there was evidence of infection, antibiotics were then also given to patients of the control group.
Results: The extent of the necroses was the same, 40%, in both groups. These necroses became infected in a median of 9.5 (treated group) and 10 days (untreated group). The clinical course, documented by the APACHE II score, showed significant improvement under antibiotic treatment (days 1-5-10: scores 15-13.0-9.5). In the (initially untreated) control group the clinical condition deteriorated significantly (days 1-5-10: score 11.5-15.0-16.0). The changes from days 1 to 5, 5 to 10 and 1 to 10 were highly significant (Wilcoxon test, P < 0.01). None of the patients in the antibiotic group died within the first 3 weeks, but 2 of the 13 in the control group died.
Conclusion: Antibiotic prophylaxis neither prevented nor delayed bacterial infection of the necrotic pancreas. But it significantly improved the clinical course if started before the onset of infection of the pancreatic necroses.