Sentence: Adding sulbactam to piperacillin resulted in increased susceptibility rates among piperacillin-resistant P. aeruginosa ( 53 - 57 % in either 2:1 or 4:1 ratios ) and A. baumannii ( 38 - 46 % in either 2:1 ratio or a fixed 8 mg/L concentration of sulbactam ) isolates .
Drug combination annotation:
[{'class': 'POS', 'spans': ['sulbactam', 'piperacillin'], 'is_context_needed': False}]