In vitro effect of mucin on polymyxin B activity against A. baumannii

The presence of mucin in the lungs can impair the availability of certain antibiotics such as polymyxins, reducing their antibacterial efficacy. The aim of this study was to characterize the effect of mucin on polymyxin B (PMB) activity against two clinical A.baumannii isolates in vitro. Time-kill (TK) experiments were performed in CAMHB, with 1% mucin or without as control, and with PMB total concentrations (CT) based on the MIC of the strain. PMB stable resistance characterization was done via MIC and whole-genome sequencing at T30h from bacteria samples that regrew in presence of antibiotic at the end of TK experiments.