Pseudomonas aeruginosa Colonization of the Gastrointestinal Tract in Patients with Cystic Fibrosis

Respiratory and fecal specimens from 111 patients with cystic fibrosis (CF) were cultured on 394 occasions to determine which site Pseudomonas aeruginosa colonizes first. By an enrichment and selection culture technique, P. aeruginosa was recovered from fecal cultures in 21 (42%) of 50 respiratory tract-positive patients but from only 3 (6.3%) of 48 respiratory tract-negative patients and from 1 (2.2%) of 45 control subjects. In 4 (22%) of the 18 patientswho became culture-positive during the study, P. aeruginosa was recovered from a fecal specimen before respiratory colonization