From the Guidelines
For a patient with pyelonephritis caused by E. coli resistant to fluoroquinolones and with a penicillin allergy, cefdinir would be the better choice for discharge. Cefdinir 300 mg twice daily for 7-14 days is recommended, with the duration depending on clinical response 1. While Augmentin (amoxicillin-clavulanate) would typically be effective against E. coli, it contains a penicillin component which poses a risk given the patient's allergy. The nature of the penicillin allergy should be clarified - if it's a mild reaction like a rash, Augmentin might be considered with caution, but if it's a severe reaction like anaphylaxis, it should be avoided entirely 1. Cefdinir, a third-generation cephalosporin, provides good coverage against gram-negative organisms including E. coli while having a lower cross-reactivity risk in penicillin-allergic patients (approximately 1-10%) 1. Ensure the patient completes the full course of antibiotics even if symptoms improve, and advise them to return if symptoms worsen or don't improve within 48-72 hours. Adequate hydration should also be emphasized during treatment. Some key points to consider when treating pyelonephritis include:
- Prompt differentiation between uncomplicated and potentially obstructive pyelonephritis is crucial, as the latter can swiftly progress to urosepsis 1.
- Fluoroquinolones and cephalosporins are the only antimicrobial agents that can be recommended for oral empiric treatment of uncomplicated pyelonephritis 1.
- Patients with uncomplicated pyelonephritis requiring hospitalisation should be treated initially with an intravenous antimicrobial regimen, such as a fluoroquinolone, an aminoglycoside (with or without ampicillin), or an extended-spectrum cephalosporin or penicillin 1. It's also important to note that the choice of antibiotic should be based on local resistance patterns and optimized 1. In this case, since the patient is allergic to penicillin and the E. coli is resistant to fluoroquinolones, cefdinir is a suitable alternative. However, it's essential to monitor the patient's response to treatment and adjust the antibiotic regimen as needed. Additionally, the patient should be educated on the importance of completing the full course of antibiotics and returning for follow-up if symptoms persist or worsen 1.
From the Research
Treatment Options for Pyelonephritis E. coli
- The patient has pyelonephritis E. coli that is resistant to fluoroquinolones and is allergic to penicillin, making treatment options limited 2, 3.
- Cefdinir and Augmentin are being considered for discharge, but it's essential to evaluate their effectiveness in treating fluoroquinolone-resistant E. coli.
Effectiveness of Cefdinir and Augmentin
- Ceftriaxone, a third-generation cephalosporin, has been shown to be as effective as concordant fluoroquinolones and significantly better than discordant fluoroquinolones in treating E. coli pyelonephritis 2.
- However, there is no direct comparison between cefdinir and Augmentin in the provided studies.
- Augmentin, a combination of amoxicillin and clavulanic acid, may not be the best option due to the patient's allergy to penicillin.
Fluoroquinolone Resistance and Treatment Outcomes
- Fluoroquinolone resistance in E. coli is a growing concern, and treatment outcomes are generally poorer when fluoroquinolones are used against resistant strains 3, 4.
- A study found that fluoroquinolone treatment of pyelonephritis caused by fluoroquinolone-resistant E. coli has a lower cure rate and involves longer hospital stays than fluoroquinolone treatment of cases caused by fluoroquinolone-sensitive E. coli 3.
Considerations for Discharge
- When choosing between cefdinir and Augmentin for discharge, it's crucial to consider the patient's allergy to penicillin and the potential effectiveness of each antibiotic against fluoroquinolone-resistant E. coli.
- Cefdinir, a third-generation cephalosporin, may be a better option due to its broader spectrum of activity and lower risk of cross-reactivity with penicillin allergies 2.