From the Guidelines
Carbapenems, particularly meropenem, imipenem, or ertapenem, are the best IV antibiotics for treating ESBL (Extended-Spectrum Beta-Lactamase) UTIs, but for complicated UTIs, ceftazidime/avibactam 2.5 g IV q8h or meropenem/vaborbactam 4 g IV q8h are recommended alternatives 1. For adults, typical dosing would be meropenem 1g IV every 8 hours, imipenem-cilastatin 500mg IV every 6 hours, or ertapenem 1g IV once daily, generally for 7-14 days depending on infection severity. Some key points to consider:
- Carbapenems are preferred because they remain stable against ESBL enzymes that inactivate most other beta-lactam antibiotics including cephalosporins and penicillins.
- For less severe cases, fosfomycin, nitrofurantoin, or aminoglycosides may be effective alternatives if susceptibility is confirmed.
- Dosage adjustments are necessary for patients with renal impairment.
- Once culture and sensitivity results are available, therapy should be narrowed to the most appropriate agent.
- Converting to oral therapy is recommended when clinically appropriate, usually after 48-72 hours of clinical improvement, to complete the treatment course and facilitate discharge from hospital care. It's also important to note that the choice of antibiotic treatment should be based on the susceptibility pattern of the isolate, and combination therapy may be considered in certain cases, such as severe infections or infections caused by multidrug-resistant organisms 1. In the case of complicated UTIs, ceftazidime/avibactam or meropenem/vaborbactam may be used as alternative treatments, with dosing recommendations of 2.5 g IV q8h or 4 g IV q8h, respectively 1. Ultimately, the choice of antibiotic treatment should be individualized based on the patient's specific needs and the susceptibility pattern of the isolate.
From the FDA Drug Label
IMIPENEM AND CILASTATIN FOR INJECTION, USP, for intravenous use ... is indicated for the treatment of the following serious infections caused by designated susceptible bacteria: ... Urinary tract infections. ( 1. 2) The best IV antibiotic for ESBL UTI is not explicitly stated in the label, but Imipenem and Cilastatin for Injection, USP (I.V.) is indicated for the treatment of urinary tract infections caused by susceptible bacteria 2.
- The dosage of Imipenem and Cilastatin for Injection (I.V.) in adult patients should be based on suspected or confirmed pathogen susceptibility.
- For adult patients with normal renal function, the recommended dosage regimens are: 500 mg every 6 hours OR 1,000 mg every 8 hours OR 1,000 mg every 6 hours. However, the label does not provide information on the effectiveness of Imipenem and Cilastatin for Injection, USP (I.V.) against ESBL-producing organisms specifically.
From the Research
Treatment Options for ESBL UTI
- Meropenem is a broad-spectrum antibacterial agent that has been shown to be effective against ESBL-producing Enterobacteriaceae 3.
- Aminoglycosides have been found to be non-inferior to carbapenems in treating bloodstream infections of urinary source caused by ESBL-producing Enterobacteriaceae 4.
- Meropenem/vaborbactam is a carbapenem/β-lactamase inhibitor combination that has been approved for use in patients with complicated urinary tract infections, including pyelonephritis 5.
- Cefepime or piperacillin/tazobactam may be considered as alternative treatment options to decrease the use of carbapenems in ESBL-producing Enterobacterales urinary tract infections 6.
Treatment Duration
- Short courses of antimicrobial treatment (≤ 7 days) may be effective in treating complicated urinary tract infections caused by ESBL-producing Enterobacterales, with no significant difference in mortality or reinfection rates compared to longer treatment courses 7.
Antibiotic Efficacy
- Meropenem has been shown to have similar efficacy to comparator antibacterial agents, including imipenem/cilastatin, clindamycin, and cefotaxime, in treating complicated urinary tract infections 3.
- Aminoglycosides have been found to be more efficacious in E. coli infections compared to other ESBL-producing Enterobacteriaceae 4.
- Meropenem/vaborbactam has been shown to be noninferior to piperacillin/tazobactam in treating complicated urinary tract infections, and may be superior in terms of overall success 5.