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 case of ranitidine - induced acute interstitial nephritis in a recipient of a cadaveric renal allograft presenting with acute allograft dysfunction within 48 hours of exposure to the drug .
### Output Text:
We report a case of <span class="chemical">ranitidine</span> - induced acute interstitial nephritis in a recipient of a cadaveric renal allograft presenting with acute allograft dysfunction within 48 hours of exposure to the drug . 