Above is a good article on CMC. The author mentions specifically that some cases occur after repeated Antibiotic treatment, for conditions such as acne.
I believe the roadmap to a cure is found in the study of tuberculosis and leprosy. 3 - 4 systemic drugs started at the same time each with different mechanisms of action. Taken for 24 -36 months has resulted in cure. Even in people genetically predisposed to it.