Antibody response to Pseudomonas aeruginosa in cystic fibrosis patients: A marker of therapeutic success?—A 30‐year Cohort study of survival in Danish CF patients after onset of chronic P. aeruginosa lung infection

Abstract
We studied the effects of increasingly intensive treatment regimens on anti‐pseudomonal antibody response and survival in five successive cohorts of a total of 157 Danish cystic fibrosis patients after they had acquired chronic P. aeruginosa lung infection. The time periods were 1971–1975 (N = 21), 1976–1980 (N = 64), 1981–1986 (N = 27), 1987–1993 (N = 26), and 1994–2000 (N = 19). During this 30‐year period, we introduced elective 2‐week courses of chemotherapy every third month in all chronically infected patients, early aggressive treatment with inhalation of colistin and oral ciprofloxacin for 3 months whenever P. aeruginosa was cultured in sputum from noncolonized patients, and inhalation of recombinant human dornase alfa. There was a significant correlation between the calendar year when chronic P. aeruginosa infection was acquired and the subsequent increase in the level of precipitins (P < 0.00001). The median number of precipitins increased by 5 per year in the oldest calendar year cohort, and 1 per year in the youngest. The median age of onset of chronic P. aeruginosa increased from 9.3 years from 1981–1986 to 13.8 years from 1987–2000. Survival after acquisition of chronic P. aeruginosa lung infection improved with time (P = 0.008). Our study shows that CF patients who are treated intensively have lower antibody responses and longer survival after acquisition of chronic P. aeruginosa lung infection. Pediatr Pulmonol. 2004; 37:427–432. © 2004 Wiely‐Liss, Inc.