From the Guidelines
For the treatment of ESBL E. coli infections, oral fosfomycin is recommended as a first-line option, particularly for uncomplicated urinary tract infections, due to its efficacy and safety profile, as supported by recent guidelines 1. When considering oral antibiotic treatment for ESBL E. coli infections, several factors must be taken into account, including the severity and location of the infection, as well as the results of susceptibility testing.
- For uncomplicated urinary tract infections, a single 3-gram dose of fosfomycin is often sufficient 1.
- In cases of more complicated infections, other options such as nitrofurantoin (100mg twice daily for 5-7 days) may be considered if the infection is limited to the urinary tract.
- For more severe cases or when first-line options are not suitable, oral carbapenems like ertapenem might be used under close medical supervision, although this is less common due to concerns about resistance and side effects.
- Trimethoprim-sulfamethoxazole or ciprofloxacin can be considered if susceptibility testing confirms their effectiveness, but resistance to these antibiotics is common among ESBL-producing bacteria 1. It's crucial to guide treatment choices by susceptibility testing results, as ESBL-producing bacteria are resistant to many common antibiotics, including penicillins and cephalosporins 1. The decision on the best treatment approach should prioritize minimizing morbidity, mortality, and improving quality of life, taking into consideration the most recent and highest quality evidence available, such as the guidelines from the European Society of Clinical Microbiology and Infectious Diseases 1.
From the Research
ESBL E. coli Oral Antibiotic Treatment
- The recommended oral antibiotic treatment options for ESBL E. coli include nitrofurantoin, fosfomycin, pivmecillinam, amoxicillin-clavulanate, finafloxacin, and sitafloxacin 2, 3, 4, 5.
- Fosfomycin has been shown to have good susceptibility against ESBL E. coli, with a susceptibility rate of 95.5% in one study 3.
- Nitrofurantoin is also effective against ESBL E. coli, with a susceptibility rate of 93% in one study 4.
- Pivmecillinam is another option, with a susceptibility rate of 96% against ESBL E. coli 4.
ESBL Klebsiella pneumoniae Oral Antibiotic Treatment
- The recommended oral antibiotic treatment options for ESBL Klebsiella pneumoniae include pivmecillinam, fosfomycin, finafloxacin, and sitafloxacin 2, 4.
- Pivmecillinam has been shown to be effective against ESBL Klebsiella pneumoniae, with a susceptibility rate of 83% in one study 4.
- Fosfomycin has a lower susceptibility rate against ESBL Klebsiella pneumoniae, with a rate of 57.6% in one study 3.
- Nitrofurantoin is not as effective against ESBL Klebsiella pneumoniae, with a susceptibility rate of 42% in one study 4.
General Considerations
- The choice of antibiotic should be based on local susceptibility patterns and the severity of the infection 2, 6.
- Carbapenems are usually regarded as the antibiotics of choice for the treatment of serious ESBL infections, but alternatives such as cephamycins, fluoroquinolones, and β-lactam/β-lactam inhibitor combinations may be considered in milder presentations 6.
- Optimized dosing of antibiotics is recommended to ensure effective treatment and minimize the risk of resistance development 6.