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: By combining information from the patient history , the physical examination , and radiologic and laboratory studies , the critical care team demonstrated that the patient had been self - treating his lithium - induced nephrogenic DI and developed neurogenic DI secondary to brain trauma .
### Output Text:
By combining information from the patient history , the physical examination , and radiologic and laboratory studies , the critical care team demonstrated that the patient had been self - treating his <span class="chemical">lithium</span> - induced nephrogenic DI and developed neurogenic DI secondary to brain trauma . 