Is nitrofurantoin (Macrobid) effective against Klebsiella pneumoniae in urinary tract infections?

Nitrofurantoin Effectiveness for Klebsiella pneumoniae Urinary Tract Infections

Nitrofurantoin activity against urinary Enterobacterales is variable and depends on local antimicrobial susceptibility for Klebsiella pneumoniae. citeturn16038517turn41997421turn42224822

Antimicrobial Susceptibility Evidence for Klebsiella pneumoniae

Reduced susceptibility of K. pneumoniae isolates to nitrofurantoin has been reported in a study integrating phenotypic testing with resistance profiling. citeturn42315052

High susceptibility to nitrofurantoin has been reported across mixed uropathogens in some contemporary urine-culture datasets, but these data do not guarantee reliable activity specifically against K. pneumoniae. citeturn16038517

In a community-care study of multidrug-resistant uropathogens that included both E. coli and K. pneumoniae, nitrofurantoin susceptibility was not reported as a K. pneumoniae–specific estimate in the abstract, limiting organism-level conclusions. citeturn42224822

Clinical Implications

Nitrofurantoin is best supported when the uropathogen is susceptible on the urine culture rather than by empiric assumption based on Enterobacterales class membership. citeturn42315052turn42224822turn16038517

Practical Approach

Urine culture with organism identification and susceptibility testing should guide selection of nitrofurantoin for UTIs where K. pneumoniae is present. citeturn42315052turn42224822