Synthesize a monitoring plan for a patient started on systemic colistin that minimizes patient harm and resistance selection. Which combination of measures is most appropriate?

• A. Initiate therapeutic drug monitoring if available, baseline and serial renal function tests, dose adjustment for renal impairment, limit duration to the minimum effective course, and coordinate with infectious diseases and stewardship for post-therapy surveillance cultures and resistance reporting.
• B. Start empirical maximal-dose colistin without baseline labs, do not adjust dose for renal function, and extend therapy indefinitely to ensure eradication regardless of toxicity risk.
• C. Switch to topical polymyxin B immediately after a single systemic dose to complete therapy since topical application eliminates the need for any monitoring while maintaining systemic levels.
• D. Avoid any monitoring because colistin side effects are unpredictable and monitoring will not change outcomes; rely on clinical judgement alone instead.

Answer: (A)