In vitro additive effect of nitrofurantoin combined with trimethoprim-sulfamethoxazole against Serratia marcescens.
The combination of nitrofurantoin (NF) plus trimethoprim-sulfamethoxazole (TMP-SMZ) was found to be additively effective against all of 12 clinical isolates of Serratia marcescens that represented 7 nosocomially significant strains, some of which were mulitple-drug-resistant. All isolates were resistant against NF; minimal inhibitory concentrations (MICs) ranged from 320 to 1,280 microgram NF/ml. The isolates were inhibited by TMP-SMZ concentrations ranging from 0.03 microgram TMP + 0.57 microgram SMZ/ml to 8 microgram TMP + 152 microgram SMZ/ml. Significantly, NF combined with TMP-SMZ proved effective against isolates with decreased susceptibility to TMP-SMZ as well. The observed in vitro additive effect of NF + TMP-SMZ might prove of clinical relevance with respect to the chemotherapy of hospital-acquired urinary tract infections due to multiple-drug-resistant strains of S. marcescens.
D004338:Drug Combinations; D004352:Drug Resistance, Microbial; D004357:Drug Synergism; D008826:Microbial Sensitivity Tests; D009582:Nitrofurantoin / Q000494:pharmacology*; D012706:Serratia marcescens / Q000187:drug effects*; D013420:Sulfamethoxazole / Q000494:pharmacology*; D014295:Trimethoprim / Q000494:pharmacology*
D004338:Drug Combinations; D009582:Nitrofurantoin; D014295:Trimethoprim; D013420:Sulfamethoxazole