From the Guidelines
Imipenem/cilastatin/relebactam is recommended for the treatment of complicated urinary tract infections (UTIs) caused by multidrug-resistant organisms, at a dose of 1.25 g IV q6h, for a duration of 5-7 days. According to the guidelines for the treatment of infections due to multidrug-resistant organisms 1, imipenem/cilastatin/relebactam is a recommended treatment option for complicated UTIs. The guidelines suggest that the choice of combination antimicrobial therapy should be based on susceptibility testing, and that extended-infusion of meropenem may be considered if the meropenem MIC is ≥ 8 mg/L. It's also important to note that imipenem/cilastatin/relebactam has not been approved by the Taiwan Food and Drug Administration as of January 2022.
Some key points to consider when using imipenem/cilastatin/relebactam for UTIs include:
- The dose and duration of treatment should be individualized based on the severity of the infection, underlying comorbidities, and initial response to therapy.
- Combination therapy with other antibiotics, such as tigecycline or polymyxin, may be considered in clinically unstable patients.
- The use of imipenem/cilastatin/relebactam should be guided by culture and sensitivity testing to ensure that the treatment is effective against the causative organism.
- The development of carbapenem-resistant organisms is a significant concern, and imipenem/cilastatin/relebactam should be used judiciously to minimize the risk of resistance.
Overall, imipenem/cilastatin/relebactam is a valuable treatment option for complicated UTIs caused by multidrug-resistant organisms, but its use should be guided by specialist expertise and based on careful consideration of the individual patient's needs and the potential risks and benefits of treatment 1.
From the FDA Drug Label
If the infection is suspected or proven to be due to a susceptible bacterial species 500 mg every 6 hours OR 1,000 mg every 8 hours Table 3: Dosage of Imipenem and Cilastatin for Injection (I.V.) for Adult Patients in Various Renal Function Groups Based on Estimated Creatinine Clearance (CLcr)
The recommended dosage of Imipenem for a UTI is 500 mg every 6 hours or 1,000 mg every 8 hours for adult patients with creatinine clearance greater than or equal to 90 mL/min.
- Key considerations:
- Dosage adjustment is necessary for patients with renal impairment.
- The maximum total daily dosage should not exceed 4 g/day.
- Imipenem is administered by intravenous infusion over 20 to 30 minutes for doses less than or equal to 500 mg, and over 40 to 60 minutes for doses greater than 500 mg 2
From the Research
Imipenem for UTI Treatment
- Imipenem is a carbapenem antibiotic that can be used to treat urinary tract infections (UTIs) caused by multidrug-resistant (MDR) organisms 3.
- The combination of imipenem and cilastatin, a β-lactamase inhibitor, has been shown to be effective in treating complicated UTIs, including those caused by MDR Gram-negative bacteria 4.
- Imipenem/cilastatin has been used to treat UTIs caused by Pseudomonas aeruginosa, with high rates of clinical and microbiologic improvement 5.
- A study comparing meropenem and imipenem/cilastatin in the treatment of complicated UTIs found that both antibiotics were effective, but meropenem had a lower rate of drug-related adverse reactions 6.
Treatment Options for UTIs
- First-line treatment options for acute uncomplicated UTIs include nitrofurantoin, fosfomycin, and pivmecillinam 3.
- Second-line options include oral cephalosporins, fluoroquinolones, and β-lactams such as amoxicillin-clavulanate 3.
- For UTIs caused by ESBL-producing Enterobacteriales, treatment options include nitrofurantoin, fosfomycin, pivmecillinam, and carbapenems such as imipenem/cilastatin 3.
- For UTIs caused by carbapenem-resistant Enterobacteriales, treatment options include ceftazidime-avibactam, meropenem/vaborbactam, and imipenem/cilastatin-relebactam 3.
Considerations for Imipenem Use
- Imipenem should be used wisely to avoid the development of resistance, particularly in the treatment of UTIs caused by MDR organisms 3.
- The use of imipenem/relebactam in complicated UTI has been evaluated, and it is considered a viable option when other treatment options are limited 4.
- Further studies are needed to evaluate the clinical efficacy of imipenem/relebactam in specific groups of UTI patients, such as those with severe urosepsis or men with suspected prostatitis 4.