What antibiotic treats Escherichia coli (E. coli) infection?

From the Guidelines

For uncomplicated urinary tract infections caused by E. coli, the most effective treatment is trimethoprim-sulfamethoxazole (Bactrim) at 160/800 mg twice daily for 3 days, as recommended by the European Association of Urology guidelines 1. When considering treatment options for E. coli infections, it's essential to prioritize the most recent and highest quality evidence. The 2024 European Association of Urology guidelines provide a comprehensive overview of suggested antimicrobial therapy regimens for uncomplicated cystitis, including first-line treatments and alternatives. Some key points to consider when treating E. coli infections include:

• The choice of antibiotic should be guided by antibiotic susceptibility testing when available, as E. coli resistance patterns vary geographically 1.
• For uncomplicated urinary tract infections, alternatives to trimethoprim-sulfamethoxazole include nitrofurantoin (Macrobid) 100 mg twice daily for 5 days, fosfomycin (Monurol) as a single 3-gram dose, or cephalosporins (e.g., cefadroxil) 500 mg twice daily for 3 days, if the local resistance pattern for Escherichia coli is <20% 1.
• Patients should complete the full course of antibiotics even if symptoms improve quickly, drink plenty of fluids, and seek medical attention if symptoms worsen or don't improve within 48 hours of starting treatment. The American College of Physicians also provides guidance on the appropriate use of short-course antibiotics in common infections, including urinary tract infections 1. However, the most recent and highest quality evidence is provided by the 2024 European Association of Urology guidelines 1, which should be prioritized when making treatment decisions.

From the FDA Drug Label

Ciprofloxacin is indicated for the treatment of complicated urinary tract infections and pyelonephritis due to Escherichia coli

• Ciprofloxacin is an antibiotic that treats Escherichia coli (E. coli) infection, specifically for complicated urinary tract infections and pyelonephritis 2.
• The drug label directly states that ciprofloxacin is effective against E. coli 2.

From the Research

Antibiotic Treatment for E. coli Infections

• The recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females includes a 5-day course of nitrofurantoin, a 3-g single dose of fosfomycin tromethamine, or a 5-day course of pivmecillinam 3.
• For ESBLs-E coli, treatment oral options include nitrofurantoin, fosfomycin, pivmecillinam, amoxicillin-clavulanate, finafloxacin, and sitafloxacin 3.
• Nitrofurantoin and fosfomycin are appropriate empirical therapy for community-acquired UTI, with resistance rates of 0.9% and 4.3% respectively 4.
• Ciprofloxacin, nitrofurantoin, amoxicillin/clavulanate, and TMP/SMX have high sensitivity rates, but resistance patterns may differ depending on the geographic area 5.
• Risk factors for TMP-SMX resistance in E. coli include recurrent UTI, genitourinary abnormalities, and TMP-SMX use within 90 days, and TMP-SMX should likely be avoided as first-line therapy in these patients 6.

Resistance Patterns

• High rates of resistance have been reported for trimethoprim-sulfamethoxazole and ciprofloxacin, precluding their use as empiric treatment of UTIs in several communities 3.
• Resistance rates for E. coli to antimicrobial agents have been reported as follows: ampicillin 66.9%, cefazolin 30.9%, cefuroxime 30.9%, ceftazidime 14.9%, cefotaxime 28%, cefepime 12%, amoxicillin-clavulanic acid 36.9%, trimethoprim-sulfamethoxazole (TMP-SXT) 20%, ciprofloxacin 49.9%, amikacin 0.3%, gentamycin 24%, nitrofurantoin 0.9%, and fosfomycin 4.3% 4.
• The frequency of ESBL-producing E. coli strains has been reported to be 24% 4.