Breaking Antimicrobial Resistance: High-Dose Amoxicillin with Clavulanic Acid for Urinary Tract Infections Due to Extended-Spectrum Beta-Lactamase (ESBL)-Producing Klebsiella pneumoniae

Background: Carbapenems are the primary treatment for urinary tract infections (UTIs) caused by extended-spectrum be-ta-lactamase (ESBL)-producing Klebsiella pneumoniae. However, the recurrence rate is high, and patients of-ten require rehospitalization. We present the results of an observational study on patients with recurrent UTIs who were treated in an outpatient setting with maximal therapeutic oral doses of amoxicillin with clavulanic acid.Material/Methods: All patients had pyuria and ESBL-producing K. pneumoniae in urine culture. The starting dosage was 2875 g of amoxicillin twice daily and 125 mg of clavulanic acid twice daily. We down-titrated the doses every 7-14 days and continued prophylactic therapy with amoxicillin/clavulanic acid at 250/125 mg for up to 3 months. We de-fined therapeutic failure as ESBL-positive K. pneumoniae in urine culture during therapy and recurrence as pos-itive urine culture with the same strain within 1 month after the end of treatment.Results: We included 9 patients: 7 kidney graft recipients, 1 liver graft recipient, and 1 patient with chronic kidney dis-ease. We observed no therapeutic failures and no recurrences in the study group during the study period. In 1 case, the patient experienced a subsequent UTI caused by ESBL-producing K. pneumoniae 4 months after com-pleting the therapy.Conclusions: In conclusion, it is possible to break the resistance of ESBL-producing K. pneumoniae strains with high doses of oral amoxicillin with clavulanic acid. Such treatment could be an alternative to carbapenems in select cases.

Automated summary

This observational study suggests that treating patients with recurrent UTIs in an outpatient setting with high doses of oral amoxicillin with clavulanic acid can effectively reduce treatment failure and recurrence.