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: However , clinical suspicion should always be supported by histological evidence in order to investigate potential alternate diagnoses such as acute or chronic rejection , interstitial fibrosis and tubular atrophy , or recurrent or de novo glomerulopathy .
### Output Text:
However , clinical suspicion should always be supported by histological evidence in order to investigate potential alternate diagnoses such as acute or chronic rejection , interstitial fibrosis and tubular atrophy , or recurrent or de novo glomerulopathy . 