Abstract
A new semisynthetic penicillin, carbenicillin, is active against gram-negative bacteria, in particular against Pseudomonas aeruginosa. Thirty-three patients suffering from manifest infections of the urinary tract due to Pseudomonas aeruginosa have been treated with carbenicillin intramuscularly for 10–20 days. Quantitative urine cultures have been performed daily during the treatment, and in a post-treatment follow-up. The Pseudomonas strains were phage-typed before and after treatment. All patients suffered from diseases favouring urinary tract infections, for example kidney or bladder stones, prostatic neoplasms or bladder paralysis due to paraplegia. Sixteen patients had an indwelling catheter. In 4 patients Pseudomonas was eliminated from the urine during treatment, and the urine remained sterile during the follow-up period of 7 days. In 12 patients Pseudomonas was eliminated, but during the follow-up period they were reinfected with other bacteria, such as E. coli, Coliform bacteria and Proteus. In 13 patients the urine was temporarily sterilized, but Pseudomonas reappeared in the urine after the cessation of treatment. Phage-typing showed that the majority of the relapses was due to the original phage-type. In 4 patients Pseudomonas was not eliminated during the treatment. The favourable clinical results obtained indicate that carbenicillin is useful for treatment of urinary tract infections caused by Pseudomonas aeruginosa.