2018
Leukopenia due to parvovirus B19 in a Crohn 's disease patient using azathioprine .
 adverse effect: Leukopenia, azathioprine
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: adverse effect 
Text: {0} 
 Entity Pairs:  Leukopenia, azathioprine 
Answer:
 adverse effect: Leukopenia, azathioprine