Antibiotic resistance is a well known public health problem, which makes the proper selection of antimicrobial agents even more critical when dealing with complicated infections.1 The importance of careful clinical judgement is highlighted in a recent case, published in the Journal of Pharmacy Practice, which describes the successful treatment of a patient with complicated urinary tract infection (UTI) involving multiple pathogens.2
The patient, a 70-year old white male in long-term care, was diagnosed with a suspected UTI after a nurse noticed his urine to be turbid, dark, and foul-smelling. Medical history indicated that the patient had a history of recurrent UTI (an extended-spectrum β-lactamase [ESBL]-producing Klebsiella pneumoniae infection was treated 2 months prior with amoxicillin/clavulanate), type 2 diabetes, hypertension, obesity, and diverticular disease.
No other symptoms were reported beyond a complaint of burning while urinating; the patient had no fever or other signs of systemic infection, his blood pressure was normal, and he had no recent catheter use. Previous lab results indicated the patient had stable renal function (CrCl: 75mL/min). Urinalysis showed he was positive for suspected UTI with urine culture still pending. He was then started on ciprofloxacin 500mg twice daily, however on day 2 urine continued to be cloudy and amber colored and the patient continued to report pain with urination.
By day 3, with urine culture still pending and the patent still in pain, he was switched to amoxicillin/clavulanate 875/125 twice daily for 10 days, after a review of the cultures from his previous UTI showed it was resistant to ciprofloxacin. By day 4 the patient reported he was feeling slightly better but urine continued to be medium dark yellow.
A review of the urine culture showed that it was positive for Escherichia coli (sensitive to all antimicrobials) and ESBL-positive K. pneumoniae (multi-drug resistant). An infectious disease clinician was brought in to assess the situation. Given that not much relief was provided from the current regimen, the ID clinician discontinued amoxicillin/clavulanate and initiated doxycycline hyclate 100mg twice daily for 14 days.