1680
Since ethambutol is actively excreted via the renal system , compromise of renal function such as due to renal tuberculosis may lead to serum concentration elevations of ethambutol sufficient to produce optic neuropathy .
 optic neuropathy, ethambutol
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:
 optic neuropathy, ethambutol