Why does antibiotic resistance in *Pseudomonas aeruginosa* rapidly increase in cystic fibrosis patients undergoing prolonged aerosolized antibiotic therapy?

💡 Explanation

Prolonged antibiotic exposure creates a strong selection pressure favoring bacteria with mutations that increase efflux pump activity. Because these pumps actively expel the antibiotic from the bacterial cell, antibiotic efficacy decreases; therefore, resistant strains become dominant, rather than other adaptation mechanisms or host-related effects.

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