What is the treatment for Escherichia coli (E. coli) positive Urinary Tract Infection (UTI)?

From the Guidelines

To treat an E. coli positive urinary tract infection (UTI), clinicians should prescribe short-course antibiotics with either nitrofurantoin for 5 days, trimethoprim–sulfamethoxazole (TMP–SMZ) for 3 days, or fosfomycin as a single dose.

Treatment Options

• For uncomplicated cystitis, the recommended treatment options are:
  • Nitrofurantoin for 5 days 1
  • Trimethoprim–sulfamethoxazole (TMP–SMZ) for 3 days 1
  • Fosfomycin as a single dose 1
• For uncomplicated pyelonephritis, the recommended treatment options are:
  • Fluoroquinolones for 5 to 7 days 1
  • TMP–SMZ for 14 days 1

Rationale

Urinary tract infections are among the most common bacterial infections requiring medical care, with Escherichia coli accounting for more than 75% of all bacterial cystitis 1. The choice of antibiotic should target this organism, and the treatment duration should depend on the type of antibiotic used.

Important Considerations

• Fluoroquinolones are highly efficacious in 3-day regimens but have a high propensity for adverse effects and should not be prescribed empirically, instead being reserved for patients with a history of resistant organisms 1.
• It is essential to complete the entire course of antibiotics even if symptoms improve before finishing, and to drink plenty of water to help flush bacteria from the system.
• Pain relievers like phenazopyridine (Azo) can help manage discomfort while the antibiotics work.
• If symptoms worsen or don't improve within 48 hours, contact your healthcare provider as you may need a different antibiotic based on culture results.

From the FDA Drug Label

To reduce the development of drug-resistant bacteria and maintain the effectiveness of sulfamethoxazole and trimethoprim tablets and other antibacterial drugs, sulfamethoxazole and trimethoprim tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to empiric selection of therapy Urinary Tract Infections For the treatment of urinary tract infections due to susceptible strains of the following organisms: Escherichia coli, Klebsiella species, Enterobacter species, Morganella morganii, Proteus mirabilis and Proteus vulgaris Fosfomycin tromethamine granules for oral solution is indicated only for the treatment of uncomplicated urinary tract infections (acute cystitis) in women due to susceptible strains of Escherichia coli and Enterococcus faecalis.

The treatment for Escherichia coli (E. coli) positive Urinary Tract Infection (UTI) is:

• Trimethoprim-sulfamethoxazole (PO) 2
• Fosfomycin (PO), but only for uncomplicated urinary tract infections (acute cystitis) in women 3

From the Research

Treatment Options for E. coli Positive UTI

• The recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females is a 5-day course of nitrofurantoin, a 3-g single dose of fosfomycin tromethamine, or a 5-day course of pivmecillinam 4.
• Second-line options include oral cephalosporins such as cephalexin or cefixime, fluoroquinolones and β-lactams, such as amoxicillin-clavulanate 4.
• For ESBL-E coli, treatment oral options include nitrofurantoin, fosfomycin, pivmecillinam, amoxicillin-clavulanate, finafloxacin, and sitafloxacin 4, 5.
• Parenteral treatment options for UTIs due to ESBLs-producing Enterobacteriales include piperacillin-tazobactam, carbapenems, ceftazidime-avibactam, ceftolozane-tazobactam, aminoglycosides, and fosfomycin 4.

Antibiotic Resistance and Treatment Efficacy

• High rates of resistance for trimethoprim-sulfamethoxazole and ciprofloxacin preclude their use as empiric treatment of UTIs in several communities, particularly if patients who were recently exposed to them or in patients who are at risk of infections with extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriales 4, 6.
• Fosfomycin was the most active agent against E. coli (resistant isolates: 5.5%), followed by nitrofurantoin (resistant isolates: 7.4%) 7.
• The estimated microbiological eradication rates for nitrofurantoin and fosfomycin were 89.7% and 83.8%, respectively 7.
• More than 95% of all ESBL producing Enterobacteriacae were sensitive to pivmecillinam, fosfomycin and nitrofurantoin 5.

Empiric Treatment Algorithm

• Amoxicillin/clavulanate and nitrofurantoin are appropriate first-line options for empiric treatment of symptomatic cystitis, with sulfamethoxazole/trimethoprim as an alternative 8.
• Nitrofurantoin was the most prescribed antibiotic (21%), followed by amoxicillin/clavulanate (19%) and ciprofloxacin (17%) 8.