In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: We report a 57 - year - old woman with end - stage renal disease receiving continuous ambulatory peritoneal dialysis ( CAPD ) , who developed slurred speech , tremor , bizarre behavior , progressive mental confusion , and 2 episodes of generalized tonic - clonic seizure ( GTCS ) after 5 doses of piperacillin / tazobactam ( 2 g / 250 mg ) were given for bronchiectasis with secondary infection .
### Output Text:
We report a 57 - year - old woman with end - stage renal disease receiving continuous ambulatory peritoneal dialysis ( CAPD ) , who developed slurred speech , tremor , bizarre behavior , progressive mental confusion , and 2 episodes of generalized tonic - clonic seizure ( GTCS ) after 5 doses of <span class="chemical">piperacillin / tazobactam</span> ( 2 g / 250 mg ) were given for bronchiectasis with secondary infection . 