The pee or not the pee: so many questions!
Resident Clinical Pearl (RCP) – May 2017
Jacqueline MacKay, R3 FMEM, Dalhousie University, Saint John, New Brunswick
The case:
A 16-month old girl with a history of fever of 39 degrees and slightly decreased oral intake for three days. She has no other symptoms of note and is a healthy, fully immunized child. Her vital signs are stable and her temperature is 37.9 after having some Advil at triage. After a careful head-to-toe examination, you note that she looks extremely well and you aren’t able identify a source for the infection.
Question:
Could this be a UTI? What investigations would be appropriate?
The overall prevalence of UTI in febrile infants age 2-24 months who have no apparent source for fever is 5%. There are some groups with higher than average risk of UTI and these groups can be identified. Additionally, the presence of another source of infection (based on clinical history and physical exam) reduces the likelihood of UTI by half.
| Individual Risk Factors: Girls | Individual Risk Factors: Boys |
|
Caucasian race Age < 12 months Temperature 39 degrees or greater Fever for 2 or more days Absence of another source of infection |
Nonblack race
Temperature 39 degrees or greater Fever for 24 hours or more Absence of another source of infection |
In girls age 2-24 months:
- 1 risk factor: probability of UTI 1% or less
- 2 risk factors: probability of UTI 2% or less
In boys age 2-24months:
- uncircumcised: probability of UTI exceeds 1% even in the absence of other risk factors
- circumcised with 2 risk factors: probability of UTI 1% or less
- circumcised with 3 risk factors: probability of UTI 2% or less
The probability of UTI increases with the addition of more risk factors, and some of the factors (such as fever duration) may change during the course of the illness, increasing the probability of UTI.
Approximately half of clinicians consider a more than 1% risk of UTI sufficient for further investigation and treatment if UTI is found, to prevent spread of infection and renal scarring.
Recommendations:
- If the clinician determines the febrile infant to have a low (<1%) likelihood of UTI, then clinical followup monitoring without testing is sufficient.
- If the clinician determines that the febrile infant is not in a low risk group (>1% risk) then there are two options: obtain a urine specimen through catheterization or suprapubic aspirate for urinalysis and culture; or to obtain a urine specimen through the most convenient means and perform a urinalysis. If the urinalysis suggests UTI (positive leukocyte esterase or nitrites, or microscopic bacteria or leukocytes), then a urine specimen should be obtained through catheterization or suprapubic aspirate.
- Consider SPA
Caveats:
- A negative urinalysis does NOT rule out UTI with certainty in children; however it is reasonable to monitor the clinical course without initiating antibiotics.
- Urine from a specimen bag CANNOT be used for culture to document UTI due to high risk of contamination.
Case conclusion:
A bag specimen was obtained for urinalysis, which was negative. After discussion with the parents, no antibiotics were prescribed and close followup was available. The child’s fever resolved within 24 hours. The urine culture was also subsequently negative.
Reference:
American Academy of Pediatrics, Subcommittee on Urinary Tract Infection, Steering Committee on Quality Improvement and Management; Roberts KB. Urinary tract infection: Clinical practice guideline for diagnosis and management of the initial UTI in febrile infants and children 2 to 24 months. Pediatrics 2011;128(
