ABSTRACT
O-demethyl-fortimicin-A-sulfate (ODMF) is a semisynthetic derivative of fortimicin-A with increased in vitro activity especially against Pseudomonas aeruginosa. This study was designed to determine the efficacy of ODMF in the treatment of UTI and to evaluate the in vitro susceptibility of bacteria isolated from the urine of patients to ODMF as compared to tobramycin (To), gentamicin (Ge) and amikacin (Ak). In 28 hospitalized patients with acute UTI, ODMF (free base) in a dose of 2 to 5 mg/kg was administered during 7 to 14 days. Every 2 days and at least 5 times during therapy, ODMF serum levels were determined (peak and trough levels) for dosage adjustment. Urine cultures were performed on day 0 and between days 2 and 4, and susceptibility of the organisms was determined. Patients were monitored for oto and nephrotoxicity. The treatment was successful in 53.5% of patients. 35.5% of patients relapsed due to severe underlying disease. ODMF was discontinued or given in reduced dosages in 10.7% of cases because of an increase in serum creatinine during therapy. Among the 37 significant strains recovered from urine, there were 54% E. coli, 10.8% Enterobacter sp., 10.8% Proteus sp., and 10.8% Pseudomonas sp. Resistance to ODMF was demonstrated in only 5.8% of strains, against 14.7% for Ge and 11.7% for To. Susceptibility of the strains was very similar for ODMF and Ak. On the whole, clinical and bacteriological results were satisfactory and did not differ from those usually obtained with aminoglycosides in the treatment of UTI due to Gram negative bacilli.
