CHARACTERISTICS OF PSEUDOMONAS-AERUGINOSA STRAINS ISOLATED FROM URINARY-TRACT INFECTIONS

Thirty-three uropathogenic strains of Pseudomonas aeruginosa were inve stigated for hemolytic activity in both bacterial broth culture filtra tes and isolate lyzates, resistance to bactericidal activity of fresh human serum, resistance to six antibiotics and plasmid DNA profile. Tw enty-four of the 33 (73 %) bacterial filtrates showed lysis of rabbit erythrocytes, as did the three after guinea-pig erythrocyte treatment. Twelve of 33 isolate lysates showed in parallel lysis of both types o f erythrocytes used. Serum resistance was found in 17 (52 %) isolates, intermediate resistance in 15 (45 %) isolates and only one isolate sh owed serum sensitivity. Resistance to antibiotics was detected as foll ows (in %): tetracycline 94, kanamycin 79, chloramphenicol 76, septrin 73, ampicillin 64, streptomycin 45, gentamicin 18. None of the isolat es investigated showed resistance to colistine. With the exception of one isolate, plasmid DNA was detected in all P. aeruginosa strains.