In cystic fibrosis the most common organism which causes early infection is

Cystic fibrosisMost common organism which causes infection is Staphylococcus.The infection that characterizes cystic fibrosis airways involves the mucus layer rather than epithelial or airway wall invasion.The unique predisposition of cystic fibrosis airways to chronic infection by Staphylococcus aureus and Pseudomonas aeruginosa is consistent with failure to clear mucus.Both mucus stasis and mucus hypoxia may contribute to the propensity for pseudomonas to grow in biofilm colonies within mucus plaques adherent to airway surfaces.(Refer: Harrison's Principles of Internal Medicine, 18th edition, pg no: 2147-2151)