Urgent Care Q&A Q1 2023

Should antibiotics be stopped in adults when a urine culture is negative? 

Although urine culture is currently regarded as the gold standard for diagnosis of UTI (albeit often retrospectively), midstream-voided urine colony counts are an imperfect diagnostic criterion for UTI. Contamination and colony counts below the laboratory’s threshold for reporting can both lead to a “negative” culture for a patient who actually has a symptomatic UTI. The most important limitation of urine cultures from a stewardship perspective is that culture results in themselves tell us nothing about whether the patient has urinary symptoms (and thus true UTI) or symptoms unrelated to the urinary tract.

Also, recent research has shown that that almost all females with typical urinary complaints and a negative culture still have an infection with E. coli.

Source: ASM and UpToDate


What is the preferred antibiotic treatment for children (infants older than one month and young children) with Urinary Tract Infection?

A cephalosporin as the first-line oral agent in the treatment of UTI in children without genitourinary abnormalities.

  • For children with a HIGH likelihood of renal involvement (ie, fever >39°C [102.2°F] with or without back pain) or immune deficiency, use a second-generation (eg, cefuroxime) or third-generation cephalosporin (e.g., cefixime, cefdinir, ceftibuten). 

The predicted probability of resistance to first-generation cephalosporins, trimethoprim-sulfamethoxazole, or amoxicillin is relatively high, and the tissue concentrations of nitrofurantoin may not be adequate to eradicate the causative organism.

– Cefixime 8 mg/kg once daily

– Cefdinir 14 mg/kg by mouth once daily

– Ceftibuten 9 mg/kg by mouth once daily

– Cefpodoxime 10 mg/kg per day by mouth divided in two doses, but no large trials have specifically evaluated the efficacy of cefpodoxime for pediatric UTI

  • For children with LOW risk of renal involvement (fever ≤39°C [102.2°F], not toxic-appearing), we prefer a first-generation cephalosporin (e.g., cephalexin 50 to 100 mg/kg per day by mouth in two divided doses) provided that the local resistance of E. coli to first-generation cephalosporins in the specific community is not high (e.g., is not ≥15 percent). 

Length of treatment: Longer course of therapy for febrile children (usually 10 days) and a short course of therapy (three to five days) for immune-competent children presenting without fever.

Source: UpToDate

Email your clinical questions to the Editors:
Tracey Davidoff, MD, FCUCM tdavidoff@coucm.org
or Cesar Mora Jaramillo, MD, FAAFP, FCUCM cmjaramillo@coucm.org
Disclaimer: This material is for educational purposes only. Medical practice and knowledge are constantly evolving and changing. This information is peer-reviewed but should not be your only source. Providers of care should use discretion when applying knowledge to any individual patient.