Pediatric Small Talk – Urine Trouble: An Approach to Pediatric UTIs
- Dec 7th, 2022
- Joe Ravera
Welcome back to Small Talk. Every first Wednesday of the month we will release high yield PEM content written by PEM talent from around the country. We hope you enjoy these reviews. Comments, questions, accolades or concerns: feel free to reach out to Joe Ravera, MD (firstname.lastname@example.org).
Author: Joe Ravera MD (@pemuvm1, Director of Pediatric Emergency Medicine, Assistant Professor of Surgery, Division of Emergency Medicine, University of Vermont Medical Center) // Reviewed by: Alex Koyfman, MD (@EMHighAK); Brit Long, MD (@long_brit)
I have (somewhat) joking called pediatric urinary tract infections- “the last thing left in pediatric emergency medicine”. As we are all aware, fever in a common chief complaint in the emergency department and in well appearing children, the overwhelming etiology of a fever is a virus1. However, it is our due diligence to consider the possibility of a bacterial etiology that would require antibiotic treatment. Many bacterial sources can be evaluated clinically (e.g. a skin or soft tissues infection) and do not require diagnostic testing other than a through exam. Additionally, the advent of vaccines (particularly Pneumococcal and Hemophilus vaccinations) has made the rate of bacteremia and meningitis extremely very low and as such well appearing children outside the neonatal do not routinely require invasive testing (e.g. blood and spinal fluid). 1 However, despite our advances in reducing pretest probability of invasive bacterial disease urinary tract infections remain a common entity seen in everyday clinical practice that both requires treatment and have complications if missed.
Whom to Test and How to Test
The decision of whom to test is probably the most difficult decision involved in pediatric UTI. If a child appears ill or has known abnormal renal/GU anatomy, they will likely need testing. In otherwise healthy, older children, life is usually made easier by two pediatric milestones. Children become verbal and potty trained around the same age (typically somewhere between 2 and 3). Once a child is verbal and potty trained the decision to test becomes easy as we can relay on more symptoms (such as dysuria) and obtaining a urine is less invasive if we are able to obtain a clean catch.
However, before these milestones, the first challenge is the paucity of identifiable urinary symptoms like dysuria or frequency. Children in this group typically have fever and abdominal symptoms such as vomiting; but it should be noted that fever alone can be a presentation of UTI. On the flip side we don’t want to test every child with a fever as the vast majority will not have a UTI.
There are clinical calculators (e.g. https://uticalc.pitt.edu/)2 that can predict a pretest probability and guide management. In my practice, I approach this question in two steps: First what is the chance the patient has a UTI? Second, what are the consequences of missing a UTI at this ED visit?
To answer the first question there are several published risk factors that increase the likelihood of a UTI include2,3,4:
- Prior UTI
- Female sex
- Younger age
- Uncircumcised male under 1 year
- Fever >39 degrees
- Fever >48 hours
- Associated vomiting
- No clear viral source
The second question is not as well studied but intuitive risk factors for a worse outcome with a missed UTI include:
- Younger age
- Concomitant medical disease
- Inability to access to primary care/return to the ED
Using a combination of the pretest probability and the outcome in conjunction with a conversation with the parents can help guide management on whether to test.
How to Test and How to Interpret the Results
While the decision of whom to test is complicated the recommendation for how to test is straight forward: a catheter or suprapubic aspiration (SPA) is the preferred method. However, SPAs are not routinely performer and different hospitals may have different comfort levels at performing catheterizations in younger children3,4. There has been some data and obtaining clean catches in young children by utilizing suprapubic and back message, the so called “Quick Wee” method. 5 If nursing staff is comfortable with this technique, it can be a reasonable alternative to catheterization. Another tip can be to utilize a point of care ultrasound (or bladder scan) pre-catheterization to confirm there is urine in the bladder prior to performing the invasive procedure. As a last resort you can use a urine bag but in this authors experience this often delays care and if the bag is positive the child, then needs a definitive urine sample with catheterization.
While the definitive test is a positive culture in the presence of symptoms, we often only have preliminary urinalysis in the emergency department. Urine dipstick is also frequently used to rapidly screen for infection. There is mixed data on younger children however, as with a UA, a dipstick at its extremes (i.e. 4+ leukocytes and positive nitrites or negative/negative) is clinically useful.6 The same calculator that estimates pretest probability will also estimate the chance a positive culture based on dipstick results (https://uticalc.pitt.edu/).2
Disposition and Anti-Microbial Therapy
There are no hard and fast criteria for whom to admit versus discharge with a suspected UTI. Suggested admission criteria are obvious and include3,4:
- Age <2 months (infants discussed below)
- Clinical urosepsis (eg, toxic appearance, hypotension, poor capillary refill)
- Patients who are immune compromised or concomitant severe medical disease
- Vomiting or inability to tolerate oral medication
- Lack of adequate outpatient follow-up (eg, no telephone, live far from hospital, etc.)
For patients with a concerning dipstick or urinalysis, antimicrobial therapy is the mainstay of treatment. E. coli is the causative agent in 80-90 percent of cases as such initial therapy with a cephalosporin is recommended3,4,7. For admitted patients’ receiving parenteral antibiotics initial therapy with Ceftriaxone 50 mg/kg is recommended. For outpatients a 2nd or 3rdgeneration cephalosporin is preferred, possible options include3,4,7:
-Cefixime 8 mg/kg once daily
-Cefdinir 14 mg/kg by mouth once daily
In more well appearing children the first-generation cephalexin 50 mg/kg divided BID may also be an appropriate choice.
Duration of therapy is also variable and somewhat symptom depended. For simple cystitis without fever in older children 3-5 days may be appropriate. For younger children, particularly with fever a longer duration (7-14 days) is recommended.3,4,7
Follow Up and After Care
Patients discharged should have follow up with there pediatrician. In older children with vulvas education about proper hygiene is critical to prevention of recurrent infections. In older children with penises a UTI would be unusual (particularly if circumcised) and requires closer follow up with the pediatrician.
In younger children the question of an undiagnosed renal anomaly (such as reflux) is often considered. It is important to let families know that these children may require an outpatient renal ultrasound.7 Ultrasound in the setting of acute infection can be difficult to interpret for reflux and as such should only be ordered if there is a clinical suspicion acute infectious complication such as an abscess.7
Special Populations: Children with Complex Medical Disease and Neonates
Children with complex medical disease and specifically complex renal or GU abnormalities require special attention. Often these children require more testing and consultation with sub specialists, and in the case of a UTI are at higher risk for atypical infections and there should be a very low threshold to manage these patients as inpatients.
In neonates a urine is obtained as part of the standard fever work up. For further reading about the latest infant fever guidelines, you can refer to a previous piece on EM docs (http://www.emdocs.net/small-talk-hot-off-the-presses-the-latest-aap-guidelines-for-the-febrile-neonate/). However since that article was written there has been a subsequent publication addressing the clinical question: what is the chance a neonate with a UTI has disseminated an infection to the CNS, so called “uromeningitis”? The upshot is that in absence of elevated inflammatory markers (ANC and Procalcitonin) the risk is extremely small, and the LP may be omitted.8
Pearls, Pitfalls and Take-Home Points
- Urine testing in preverbal non toilet trained kids is based on the pre-test probability of disease and the risk of a delayed diagnosis.
- There is no hard and fast rule for admission when a patient has a UTI, it is based on a myriad of clinical factors.
- Imagining in the ED should be reserved for patients with a suspected infectious complication (e.g. renal abscess).
- Neonates with a positive UA have an extremely low risk of meningitis if they have negative inflammatory markers.
- Cioffredi LA, Jhaveri R. Evaluation and Management of Febrile Children: A Review. JAMA Pediatr. 2016 Aug 1;170(8):794-800.
- Shaikh N, Hoberman A, Hum SW, Alberty A, Muniz G, Kurs-Lasky M, Landsittel D, Shope T. Development and Validation of a Calculator for Estimating the Probability of Urinary Tract Infection in Young Febrile Children. JAMA Pediatr. 2018 Jun 1;172(6):550-556.
- SUBCOMMITTEE ON URINARY TRACT INFECTION. Reaffirmation of AAP Clinical Practice Guideline: The Diagnosis and Management of the Initial Urinary Tract Infection in Febrile Infants and Young Children 2-24 Months of Age. Pediatrics. 2016 Dec;138(6):e20163026
- Kaufman J, Temple-Smith M, Sanci L. Urinary tract infections in children: an overview of diagnosis and management. BMJ Paediatr Open. 2019 Sep 24;3(1)
- Kaufman J, Fitzpatrick P, Tosif S, Hopper SM, Donath SM, Bryant PA, Babl FE. Faster clean catch urine collection (Quick-Wee method) from infants: randomised controlled trial. BMJ. 2017 Apr 7;357:j1341.
- Glissmeyer EW, Korgenski EK, Wilkes J, Schunk JE, Sheng X, Blaschke AJ, Byington CL. Dipstick screening for urinary tract infection in febrile infants. Pediatrics. 2014 May;133(5):e1121-7.
- Mattoo TK, Shaikh N, Nelson CP. Contemporary Management of Urinary Tract Infection in Children. Pediatrics. 2021 Feb;147(2):e2020012138.
- Mahajan P, VanBuren JM, Tzimenatos L et. al. Pediatric Emergency Care Applied Research Network (PECARN). Serious Bacterial Infections in Young Febrile Infants With Positive Urinalysis Results. Pediatrics. 2022 Oct 1;150(4):e2021055633.