Aztreonam versus cefamandole in the treatment of urinary tract infections.
The in vivo efficacy and safety of aztreonam compared to that of cefamandole was randomly and prospectively studied in the treatment of 30 patients suffering from recurrent urinary tract infections with a patient ratio of 2 aztreonam to 1 cefamandole. The mean age was 51.6 +/- 15.4 and 59.8 +/- 13 years respectively. Both antibiotics were given at a dose of 1 g, 8 hourly i.m. for 7-13 days. Sixty-seven percent versus 70% of the patients given aztreonam and cefamandole respectively were suffering from upper urinary tract infections. X ray abnormalities predisposing to relapse or reinfections were present in 88% vs 80% of the patients, while all patients had typical symptoms of urinary tract infections, with high fever (greater than or equal to 38.5 degrees C) reported in 70% and 60% of the patients in the two treatment groups respectively. Escherichia coli and Proteus mirabilis were the predominant isolates in urine cultures. During treatment all patients responded favourably both clinically and bacteriologically, while after a 6-week follow-up 20% versus 30% relapsed clinically with 15% vs 30% bacteriologic relapses in the two groups, but only in patients suffering from upper urinary tract infections. No development of bacterial resistance was observed in the relapses, while mainly Enterococcus spp was implicated in reinfections. No appreciable side effects of toxicity were observed. It was concluded that aztreonam is a promising new antibiotic that deserves further clinical trials in systemic infections.