Trimethoprim-sulphamethoxazole in urinary tract infection due to Streptococcus faecalis.

In-vitro sensitivities were performed on 140 specimens of urine which grew Streptococcus faecalis of more than 100 000 organisms/ml between March 1970 and February 1971. Although the combination of trimethoprim and sulphamethoxazole definitely appeared to be more effective than sulphonamide alone and as effective as ampicillin, its use for more than two weeks in 14 cases of uncomplicated urinary tract infection due to Streptococcus faecalis led to development of resistance. As in these cases organisms were resistant to sulphonamide to start with, it is suggested that the combination should be used in prolonged treatment only where the organisms are sensitive to both the individual antibiotics. Ampicillin is still the drug of choice in urinary tract infection due to Streptococcus faecalis. The alternative appears to be rotational therapy with other potent antibiotics.