2721
This is the first description , to our knowledge , of ductopenia apparently caused by clindamycin .
 ductopenia, clindamycin
Please list all entity pairs containing a certain relationship in the given options.Output format is "word1, word2; word3, word4". 
Option: adverse effect 
Text: {0} 
Answer:
 ductopenia, clindamycin