From the Guidelines
Imipenem should be reserved for complicated urinary tract infections (UTIs) caused by multidrug-resistant organisms, and its use should be guided by culture results and local resistance patterns, as recommended by recent guidelines 1. The standard dosing for adults with normal renal function is 500 mg intravenously every 6 hours, usually administered with cilastatin (as Imipenem-Cilastatin) to prevent renal metabolism of imipenem. Some key points to consider when using imipenem for UTIs include:
- Treatment duration typically ranges from 7-14 days depending on infection severity, with a shorter duration considered in certain cases 1.
- Imipenem provides broad-spectrum coverage against most gram-positive and gram-negative bacteria, including Pseudomonas aeruginosa and extended-spectrum beta-lactamase (ESBL) producing organisms.
- Due to concerns about antimicrobial resistance, imipenem should not be used for uncomplicated UTIs or as empiric therapy unless patient factors strongly warrant it, as emphasized in guidelines such as those from the European Association of Urology 1.
- Potential side effects include seizures (especially at higher doses or in patients with CNS disorders or renal impairment), gastrointestinal disturbances, and allergic reactions.
- Renal dosing adjustments are necessary for patients with creatinine clearance below 70 mL/min. It is essential to note that the use of imipenem should be based on the most recent and highest-quality evidence, and guidelines such as those from the European Association of Urology 1 should be consulted for the latest recommendations on the treatment of UTIs.
From the FDA Drug Label
Imipenem and Cilastatin for Injection, USP for intravenous use is a combination of imipenem, a penem antibacterial, and cilastatin, a renal dehydropeptidase inhibitor, indicated for the treatment of the following serious infections caused by designated susceptible bacteria: ... Urinary tract infections. ( 1. 2)
Imipenem is indicated for the treatment of urinary tract infections (UTIs) 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.
- The recommended dosage regimens for adult patients with normal renal function are:
- 500 mg every 6 hours
- 1,000 mg every 8 hours
- 1,000 mg every 6 hours A reduction in dose must be made for patients with impaired renal function.
From the Research
Role of Imipenem in UTI Treatment
- Imipenem, a carbapenem antibiotic, is used to treat urinary tract infections (UTIs) caused by antibiotic-resistant Gram-negative bacteria 3.
- It is a recommended treatment option for UTIs due to AmpC-β-lactamase-producing Enterobacteriales, ESBLs-E coli, and ESBLs-Klebsiella pneumoniae 3.
- Imipenem is also used to treat UTIs caused by carbapenem-resistant Enterobacteriales (CRE) and multidrug-resistant (MDR)-Pseudomonas spp. 3.
Efficacy of Imipenem in UTI Treatment
- Studies have shown that imipenem is effective in treating complicated UTIs, with clinical improvement and microbiologic eradication rates of 95.5% and 87.8%, respectively 4.
- Imipenem has been shown to be safe and effective in treating UTIs caused by Pseudomonas aeruginosa, with no drug-related clinical adverse effects reported 5.
- The combination of imipenem and cilastatin has been used to treat complicated UTIs, with good therapeutic results and no significant adverse effects 4, 5.
Recommendations for Imipenem Use in UTI Treatment
- Imipenem should be used as a first-line empirical therapy for severe bacterial infections in urology, due to its wide spectrum of antibacterial action 4.
- The use of imipenem should be based on local resistance patterns, patient-specific factors, and pharmacokinetic and pharmacodynamic principles 6.
- Imipenem/relebactam can be used in complicated UTI when other treatment options are limited, but further studies are needed to evaluate its clinical efficacy in specific patient groups 7.