From the Guidelines
Yes, a repeat urine culture is indicated if symptoms persist despite a negative initial culture.
Rationale
- The European Association of Urology guidelines suggest that a urine culture is recommended in situations where symptoms do not resolve or recur within 4 weeks after completion of treatment 1.
- The American Urological Association guideline also recommends repeating urine cultures to guide further management when UTI symptoms persist following antimicrobial therapy 2.
- Additionally, if a patient has persistent symptoms despite treatment, repeating the urine culture to assess for ongoing bacteriuria before prescribing additional antibiotics is recommended 3.
Key Points
- Repeat urine culture is necessary to guide further management and avoid unnecessary treatment of patients with persistent UTI/pain symptoms who are culture-negative 2.
- Symptom clearance is sufficient, and microbiological reassessment (i.e., repeat urine culture) after successful UTI treatment is not endorsed as it may lead to overtreatment 2.
- If symptoms persist beyond seven days, it is reasonable to repeat a urine culture, and a second antibiotic can be given empirically only after a urine sample is obtained for culture 2.
From the Research
Repeat Urine Culture Indication
- A repeat urine culture may be indicated if symptoms persist despite a negative initial culture, as the initial culture may be a false-negative result 4.
- Studies have shown that repeat urine cultures can provide valuable information for diagnosis and treatment, especially in cases where the initial culture is negative or inconclusive 5, 6.
Predictive Factors for Positive Repeat Culture
- Certain factors, such as age less than 1 year, aetiological agents Enterococci spp., fever of more than 72 h, inappropriate antibiotics, and kidney, ureter, and bladder anomalies, may indicate a positive repeat culture 7.
- A prior negative culture and negative urinalysis may also be predictive of another negative culture 8.
Cost-Effectiveness of Repeat Urine Culture
- The cost-effectiveness of repeat urine cultures during antibiotic therapy for febrile urinary tract infection has been evaluated, and it was found that a repeat urine culture may be useful in certain cases, such as in children with risk factors for a positive repeat culture 7.
- However, the estimated laboratory charges for inappropriate repeat urine cultures can be significant, highlighting the need for diagnostic stewardship and optimization of antimicrobial use 6.
Clinical Correlation and Microbiological Profile
- Repeat urine cultures can provide information on the microbiological profile and clinical correlation, which can help guide treatment and prevent unnecessary antibiotic use 5.
- The importance of requesting repeat urine samples for an accurate urine culture report has been emphasized, especially in cases where the initial culture shows significant bacteriuria or multiple types of colonies 5.