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: HP failed to accentuante progression of renal failure and in fact tended to increase GFR and decrease plasma creatinine levels in lithium pretreated rats .
### Output Text:
HP failed to accentuante progression of renal failure and in fact tended to increase GFR and decrease plasma <span class="chemical">creatinine</span> levels in <span class="chemical">lithium</span> pretreated rats . 