What are alternative antibiotics for Urinary Tract Infections (UTI) in patients with a Cephalosporin (antibiotic) allergy?

From the Guidelines

For patients with cephalosporin allergy who need treatment for a urinary tract infection (UTI), Fosfomycin 3g single-dose sachet is a recommended option, as it is convenient and effective for uncomplicated cystitis, according to the European Association of Urology guidelines 1. When considering alternative antibiotic options, it's essential to weigh the benefits and risks of each choice. Nitrofurantoin (Macrobid) 100mg twice daily for 5-7 days is a good first-line option for uncomplicated UTIs, as it concentrates well in the urinary tract and has low resistance rates. Trimethoprim-sulfamethoxazole (Bactrim DS) one double-strength tablet twice daily for 3 days is another effective choice, though local resistance patterns should be considered. Some key points to consider when selecting therapy include:

• Verifying the nature of the cephalosporin allergy, as true cross-reactivity with other beta-lactams occurs in only about 10% of patients
• Considering local antibiogram data when selecting therapy
• Ensuring appropriate follow-up for patients with persistent symptoms
• Being aware of the potential for cross-reactivity between cephalosporins and other beta-lactams, such as ceftazidime, as noted in the 2022 practice parameter update on drug allergy 1 In cases of known organism sensitivities, amoxicillin or amoxicillin-clavulanate may be appropriate if the pathogen is susceptible. For pregnant patients, nitrofurantoin (avoiding in third trimester) or fosfomycin are preferred options. It's also important to note that aztreonam may be administered without prior testing in patients with a history of penicillin or cephalosporin allergy, unless there is a history of ceftazidime allergy, as suggested by the 2022 practice parameter update on drug allergy 1.

From the FDA Drug Label

The mean peak serum concentration achieved at steady-state in human adults receiving 500 mg orally every 12 hours is 2.97 μg/mL, and 4. 56 μg/mL following 400 mg intravenously every 12 hours.

Levofloxacin has in vitro activity against Gram-negative and Gram-positive bacteria fections as described in Indications and Usage (1): Gram-PositiveBacteria Enterococcus faecalis Staphylococcus aureus (methicillin-susceptible isolates) Staphylococcus epidermidis (methicillin-susceptible isolates) Staphylococcus saprophyticus Streptococcus pneumoniae (including multi-drug resistant isolates [MDRSP] )1 Streptococcus pyogenes Gram-Negative Bacteria Enterobacter cloacae Escherichia coli Haemophilus influenzae Haemophilus parainfluenzae Klebsiella pneumoniae Legionella pneumophila Moraxella catarrhalis Proteus mirabilis Pseudomonas aeruginosa Serratia marcescens

Antibiotics for UTI in patients with cephalosporin allergy:

• Ciprofloxacin and levofloxacin are potential alternatives for treating UTIs in patients with cephalosporin allergy, as they have shown efficacy against various Gram-negative and Gram-positive bacteria, including Escherichia coli, which is a common cause of UTIs.
• However, it is essential to consider the patient's specific medical history, the severity of the allergy, and the local resistance patterns before making a decision.
• It is also crucial to note that fluoroquinolones, including ciprofloxacin and levofloxacin, may have potential side effects and should be used judiciously.
• The choice of antibiotic should be based on the results of susceptibility testing, whenever possible, to ensure the most effective treatment. 2 3

From the Research

Treatment Options for UTI in Patients with Cephalosporin Allergy

• For patients with a cephalosporin allergy, alternative treatment options for urinary tract infections (UTIs) include nitrofurantoin, fosfomycin, and pivmecillinam 4.
• Nitrofurantoin is a suitable option for uncomplicated UTIs, with a high susceptibility rate against common UTI pathogens, including Escherichia coli 5, 6.
• Fosfomycin and pivmecillinam are also effective against UTIs caused by extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriales 4.
• For patients with a cephalosporin allergy, fluoroquinolones, such as ciprofloxacin and levofloxacin, may not be the best option due to high resistance rates 5.
• Other treatment options for UTIs in patients with cephalosporin allergy include amoxicillin-clavulanate, finafloxacin, and sitafloxacin, although their use may be limited by resistance patterns 4.

Considerations for Treatment

• The choice of antibiotic therapy should be guided by local susceptibility patterns and the patient's allergy history 4.
• It is essential to use antibiotics wisely to avoid the development of resistance 4.
• Patient and physician characteristics, such as age and specialty, can influence the choice of antibiotic therapy and guideline concordance 7.
• Education and feedback on prescription habits can help increase guideline concordance and reduce the misuse of antibiotics 7.