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 also caused proteinuria and systolic hypertension in absence of glomerulosclerosis .
### Output Text:
<span class="chemical">Lithium</span> also caused proteinuria and systolic hypertension in absence of glomerulosclerosis . 