In the sentence extracted from biomedical literature, identify all the disease entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="disease"> to denote a disease.

### Input Text: Complete hypoxanthine - guanine phosphoribosyl - transferase ( HPRT ) deficiency in humans results in the Lesch - Nyhan syndrome which is characterized , among other features , by compulsive self - injurious behavior .
### Output Text:
<span class="disease">Complete hypoxanthine - guanine phosphoribosyl - transferase ( HPRT ) deficiency</span> in humans results in the <span class="disease">Lesch - Nyhan syndrome</span> which is characterized , among other features , by compulsive self - injurious behavior . 