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: Lithium - treated WT mice had 19 - fold increased urine output whereas treated PKCa KO animals had a 4 - fold increase in output .
### Output Text:
<span class="chemical">Lithium</span> - treated WT mice had 19 - fold increased urine output whereas treated PKCa KO animals had a 4 - fold increase in output . 