LYZ and cystic fibrosis: P. aeruginosa, a cause of nosocomial infections and of chronic respiratory infections in patients with cystic fibrosis, was also the object of a study aimed to improve the modest basal effect of lysozyme (from egg whites) by subinhibitory doses of colistin, an antibiotic of the polymyxin family and active as a permeabilizing agent [245,246].