[Serodiagnosis of Pseudomonas aeruginosa infections in mucoviscidosis: comparative study of Western blotting, ELISA exotoxin A and ELISA phospholipase C].

Anti-Pseudomonas aeruginosa antibodies were studied by Western Blot, ELISA-exotoxin A and ELISA-phospholipase C for 91 serums from 31 patients with cystic fibrosis. More, for the two enzyme-linked immunosorbent assays, 44 serums from 44 healthy individuals were studied as controls. The study of these three parameters revealed the followings: with no infection by Pseudomonas aeruginosa all the results were negative, at the beginning of the infection, anti-exotoxin A antibodies appeared in first, followed in some cases by the reactions of Western Blot, anti-phospholipase C antibodies became positive at last and went on a par with the installation of the chronic characteristic of the infection, as soon as the chronicity were indisputable, the three methods revealed elevated serum antibodies amounts. Generally there was a correlation between detected antibodies and Pseudomonas aeruginosa isolation in sputum. Among these three methods, ELISA-exotoxin A appeared to be the most interesting because of its good reproducibility and its early positivity, before the others methods and sometimes before Pseudomonas aeruginosa isolation. It would be a significant argument to establish as soon as possible an antimicrobial therapy.