Antibiotic Therapy for 7 Days Effective for Most Patients With Complicated UTI

Seven days of antibiotic therapy is likely sufficient for hospitalized patients with complicated urinary tract infection (cUTI), though some patients may need up to 10 days of therapy. These study results were published in Clinical Infectious Diseases.

Researchers conducted a retrospective study to determine the optimal duration of antibiotic therapy among adults with cUTI at 24 hospitals in the United States. The primary outcome was the risk for recurrent infection with the same causative pathogen within 30 days of therapy completion. Patients without associated bacteremia were excluded. Included patients (N=1099) were divided into groups by duration of antibiotic therapy (7 [n=265], 10 [n=382], or 14 [n=452] days). Propensity-score adjusted inverse probability treatment weighting (IPTW) was used to balance covariates between the groups.

Among patients who received 10 vs 14 days of therapy, the median age was 70 (IQR, 60-80) and 68 (IQR, 56-77) years, 65% and 58% were 65 years and older, 64% and 65% were men, 55% and 53% were White, and 19% and 26% were severe immunocompromised, respectively. For patients who received 7 vs 14 days of therapy, the median age was 72 (IQR, 63-81) and 68 (IQR, 56-77) years, 73% and 58$ were 65 and older, 71% and 65% were men, 59% and 56% were White, and 16% and 26% were severely immunocompromised, respectively.

Overall, the most commonly identified causative pathogens were Escherichia coli (59%), followed by Klebsiella pneumoniae (16%), Proteus mirabilis (8%), and Pseudomonas aeruginosa (6%). There were 143 (13%) patients infected with extended-spectrum β-lactamase-producing pathogens.  

In the IPTW analysis, there was no increase in the risk for recurrent infection among patients who received 10 vs 14 days of antibiotic therapy (adjusted odds ratio [aOR], 0.99; 95% CI, 0.52-1.87). However, recurrent infection risk was significantly increased among patients who received 7 vs 14 days of antibiotic therapy (aOR, 2.54; 95% CI, 1.40-4.60; P =.002). Of note, the risk for recurrent infection did not significantly differ between patients in the 7- vs 14-day groups after the analysis was restricted to those who either received intravenous (IV) antibiotics or were switched to agents with high bioavailability (aOR, 0.76; 95% CI, 0.38-1.52).

Limitations of this study include the retrospective design, the inability to confirm treatment adherence, and potentially missing data.

According to the researchers, “More data are needed to determine if patients treated with oral beta-lactam agents administered at dosages and frequencies that mimic IV beta-lactam agents can also be successfully treated with 7 days of antibiotics.”

Disclosure: Some authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.