title: Unexpected induction of resistant Pseudomonas aeruginosa biofilm to fluoroquinolones by diltiazem: a new perspective of microbiological drug-drug interaction.
abstract: The increase of multi-drug resistant Pseudomonas aeruginosa infections is a worldwide dilemma. At the heart of the problem is the inability to treat established P. aeruginosa biofilms with standard antibiotic therapy, including fluoroquinolones. We address a previously unstudied question as to the effect of a commonly prescribed calcium channel blocker (CCB) diltiazem on the biofilm growth. Real-time monitoring of the overall growth and killing of P. aeruginosa biofilm during fluoroquinolones therapy in the presence and absence of diltiazem was performed. In this study, we demonstrate that for P. aeruginosa biofilms, resistance to the first-line fluoroquinolones may be induced by the commonly prescribed calcium channel blocker diltiazem.
authors.affiliation: University of Minnesota, Duluth, College of Pharmacy, Pharmacy Practice and Pharmaceutical Sciences, 1110 Kirby Dr. Life Sciences 232, Duluth, MN 55812, USA.
authors.forename: Walid F
authors.initials: WF
authors.lastname: Elkhatib
authors.forename: Virginia L
authors.initials: VL
authors.lastname: Haynes
authors.forename: Ayman M
authors.initials: AM
authors.lastname: Noreddin
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology; D004110:Diltiazem / Q000494:pharmacology*; D004338:Drug Combinations; D004347:Drug Interactions; D024881:Drug Resistance, Bacterial; D024841:Fluoroquinolones / Q000494:pharmacology*; D018613:Microscopy, Confocal; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D002121:Calcium Channel Blockers; D004338:Drug Combinations; D024841:Fluoroquinolones; D002939:Ciprofloxacin; D004110:Diltiazem