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

From the Guidelines

Nitrofurantoin is not the preferred choice for treating Klebsiella pneumoniae urinary tract infections (UTIs) due to increasing resistance rates and variable susceptibility patterns. According to the guidelines from the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases 1, nitrofurantoin is effective against certain strains of bacteria that cause uncomplicated cystitis, but its efficacy against Klebsiella pneumoniae is not well-established. The studies included in the guidelines demonstrate that nitrofurantoin has similar clinical cure rates to other antibiotics such as trimethoprim-sulfamethoxazole and ciprofloxacin for treating acute uncomplicated cystitis, but the bacterial cure rates and susceptibility patterns for Klebsiella pneumoniae are not specifically addressed.

Some key points to consider when treating UTIs with nitrofurantoin include:

• The clinical cure rate with nitrofurantoin for acute uncomplicated cystitis is 88% - 93% 1
• The bacterial cure rate with nitrofurantoin for acute uncomplicated cystitis is 81% - 92% 1
• Nitrofurantoin is not recommended for pyelonephritis or complicated UTIs due to its limited tissue penetration outside the urinary tract
• Local resistance patterns and culture and sensitivity testing should be considered before prescribing nitrofurantoin for UTIs

Alternative antibiotics such as trimethoprim-sulfamethoxazole, fluoroquinolones, or cephalosporins may be needed to treat Klebsiella pneumoniae UTIs, especially if resistance to nitrofurantoin is suspected or confirmed. In general, the choice of antibiotic for treating UTIs should be guided by local resistance patterns, patient factors, and the severity of the infection.

From the Research

Nitrofurantoin Coverage for Klebsiella Pneumoniae UTI

• The effectiveness of nitrofurantoin in covering Klebsiella pneumoniae UTI is a topic of discussion in various studies 2, 3, 4, 5.
• According to a study published in 2020, nitrofurantoin is not listed as a first-line treatment option for UTIs due to ESBL-producing Klebsiella pneumoniae, but rather as an option for ESBL-E coli 2.
• A 2011 study found that nitrofurantoin had good activity against ESBL-producing E. coli, but its effectiveness against ESBL-producing Klebsiella pneumoniae was not as strong, with a susceptibility rate of only 2.4% 3.
• Another study published in 2019 investigated the resistance mechanism of a uropathogenic Klebsiella pneumoniae isolate to nitrofurantoin and found that efflux pumps AcrAB and OqxAB contributed to the resistance 4.
• A 2022 study reported that the susceptibility of Klebsiella pneumoniae to nitrofurantoin was 64.1% in a long-term care facility, making it a less effective option compared to other antibiotics such as amoxicillin/clavulanate 5.

Treatment Options for Klebsiella Pneumoniae UTI

• The treatment options for UTIs due to ESBL-producing Klebsiella pneumoniae include oral antibiotics such as pivmecillinam, fosfomycin, finafloxacin, and sitafloxacin, as well as parenteral options like piperacillin-tazobactam, carbapenems, and ceftazidime-avibactam 2.
• Nitrofurantoin may not be the best option for treating Klebsiella pneumoniae UTI due to its limited susceptibility and potential resistance mechanisms 3, 4.
• The choice of antibiotic should be guided by local susceptibility patterns and the specific characteristics of the infecting organism 2, 5.