PREVALENCE OF MUCOID STRAINS OF PSEUDOMONAS-AERUGINOSA IN BACTERIOLOGICAL SPECIMENS FROM PATIENTS WITH CYSTIC-FIBROSIS AND PATIENTS WITH OTHER DISEASES
The relative prevalence of mucoid strains compared with non-mucoid strains of P. aeruginosa was investigated in all routine bacteriological specimens received in a department of clinical microbiology during 1973. P. aeruginosa was isolated from 1054 of the specimens (5.7%) representing 53 patients with cystic fibrosis (551 isolates) and 169 patients with other diseases (503 isolates). The relative prevalence of mucoid strains was significantly higher in specimens from patients with cystic fibrosis (80%) than in specimens from patients with other diseases (3%). Considering patients without cystic fibrosis, the relative prevalence of mucoid strains was low in specimens from all anatomical regions, and no special preference of these strains for the respiratory tract was demonstrated in these patients, in contrast to the situation in patients with cystic fibrosis. Alternation between mucoid strains and non-mucoid strains in subsequent specimens was observed in 33 of the patients.