Urinary tract infection

Disclaimer

These guidelines have been produced to guide clinical decision making for the medical, nursing and allied health staff of Perth Children’s Hospital. They are not strict protocols, and they do not replace the judgement of a senior clinician. Clinical common-sense should be applied at all times. These clinical guidelines should never be relied on as a substitute for proper assessment with respect to the particular circumstances of each case and the needs of each patient. Clinicians should also consider the local skill level available and their local area policies before following any guideline. 

Read the full PCH Emergency Department disclaimer.

Aim

To guide staff with the assessment and management of urinary tract infection in children.

Definition

Urinary tract infection (UTI) refers to a bacterial infection in the bladder (cystitis), or kidneys and ureters (pyelonephritis).

Background

  • Urinary tract infections in childhood are common and can be potentially serious in the first few years of life
  • The diagnosis of UTI should be considered in all febrile infants and young children, and in all infants with fever without focus.

Urinary tract infection management flowchart. Click to enlarge.

Assessment

  • A reliable urine specimen is vital to confirm the diagnosis. Urine bags must not be used (high contamination rate)
  • Suprapubic aspiration is the gold standard in infants less than 6 months, however catheter specimens can be used. In children over 6 months, catheter specimens are the preferred choice if a clean catch specimen has not been achieved by 45 minutes
  • In febrile young children who have a definite clear alternative clinical diagnosis, it is not necessary to check a urine collection in order to exclude a UTI.

History

  • Fever may be present, particularly fever without apparent source
  • Irritability
  • Poor feeding
  • Vomiting
  • Jaundice (in neonates)
  • In older children symptoms can include dysuria, urinary frequency, and urinary incontinence.

Investigations

  • Urinalysis is not accurate in infants under 12 months - so cannot be used to exclude a UTI. The only urinalysis results reliably predictive of a UTI are the leukocyte esterase and nitrites.
  • Urine should be sent to the laboratory for microscopy and culture.
    • Send urgently in infants less than 6 weeks of age in whom a UTI is suspected
    • After hours a microbiology technician will need to be called in after discussing with the on call microbiologist
  • A reliable urine specimen is vital to confirm the diagnosis SPA, CSU, clean catch or MSU (in older children)
  • Urine cultures may be negative if there is previous antibiotic treatment
  • Children who are systemically unwell and all infants less than 3 months should have blood tests including:
    • FBC
    • blood cultures
    • CRP
    • UEC.
  • Lumbar punctures should be done in neonates and children less than 6 weeks.

Investigations for age group

Birth to 6 weeks of age

6 weeks to 3 months of age Over 3 months of age
  • FBC, CRP, UEC, blood cultures
  • Urine - SPA
  • Lumbar puncture
  • FBC, CRP, UEC, blood culture
  • Urine - SPA best,  but can do in-out catheter
  • Consider lumbar puncture only if toxic signs present

Toxic signs present:

  • FBC, CRP, UEC, blood cultures
  • Urine - SPA or catheter in children less than 6 months, or catheter if you have waited for greater than 45 minutes for a clean catch in older children
  • Consider lumbar puncture (if clinically indicated)

Appears unwell but no toxic signs:

  • Urine - SPA or catheter in children less than 6 months, or catheter if you have waited for greater than 45 minutes for a clean catch in older children

Appears well:

  • Urine - SPA or catheter in children less than 6 months, or catheter if the wait for a clean catch urine in older children is greater than 45 minutes

Management

Management for age group

For more specific antibiotic information (ChAMP urinary tract infection).

Birth to 6 weeks of age 6 weeks to 3 months of age Over 3 months of age
  • Admit under general paediatric team
  • Intravenous antibiotics: Amoxycillin and Gentamicin
  • Admit under general paediatric team
  • Intravenous antibiotics: Amoxycillin and Gentamicin

Toxic signs present:

  • Admit under general paediatric team
  • Intravenous antibiotics: Amoxycillin and Gentamicin or Ceftriaxone

Appears unwell but no toxic signs:

  • Consider IM antibiotics: Gentamicin or Ceftriaxone
  • Discharge home on oral antibiotics: Cephalexin or Cotrimoxazole or Augmentin Duo
  • GP follow up in 48 to 72 hours to check urine culture and sensitivity
  • Request renal US based on child's age as per referral instructions below

Appears well:

  • Discharge home on oral antibiotics: Cephalexin or Cotrimoxazole or Augmentin Duo
  • GP follow up in 48 to 72 hours to check urine culture and sensitivity
  • Request renal US based on child's age as per referral instructions below

Medications

Oral antibiotic choices for patients who are being discharged from the Emergency Department

Augmentin Duo 25mg/kg twice daily (to a maximum of 875mg of amoxycillin component)

or

Cotrimoxazole 4mg/kg twice daily(to a maximum dose of 160mg trimethoprim)

or

Cephalexin 12.5mg/kg 6 hourly (maximum 500mg)

The duration of treatment should be:

    • 5 days for children
    • 7 days if they are more unwell
    • 10 days for infants under 12 months.
Intramuscular (IM) antibiotic choices for patients who are being discharged from the emergency department

Gentamicin 6mg/kg (to a maximum of 480mg)

or

Ceftriaxone 50mg/kg (maximum 2g)

Intravenous antibiotic choices for children being admitted to hospital

Amoxycillin 50mg/kg 6 hourly (maximum 1g) plus Gentamicin 7.5mg/kg (< 10 years old) or 6mg/kg (>10 years old) (maximum 480mg

or

Ceftriaxone 50mg/kg once daily  (maximum 2g) – if penicillin allergy

  • See Antibiotics UTI: ChAMP Empiric Guideline for further information.
  • Prophylaxis is not routinely used after the first documented UTI

Referrals and follow up

Renal tract ultrasounds

  • All children less than 3 years presenting with a first UTI should have a renal tract ultrasound
  • A renal tract ultrasound is not always necessary for children aged 3 years or older with a simple UTI, however:
    • children of any age with recurrent urinary tract infections should have a renal tract ultrasound (non urgent)
    • children any age with an atypical UTI or UTI responding poorly to treatment should have a renal tract ultrasound (urgent).

GP follow up

  • All children presenting with a UTI should have a GP follow up and a GP letter completed. (xxxxlink to GP letter)
  • In children greater than 6 months, GP will arrange an outpatient renal tract US.

Referral to General Paediatric Team

  • Infants < 6 months presenting with a UTI should be referred to the General Paediatric Outpatient Clinic at PCH. Complete an internal referral form and a PCH radiology request form should be completed for a renal tract ultrasound and  placed with the Outpatient Clinic referral form in the ED consultant’s office
  • The consultant checking results will send these off if a UTI is proven on culture
  • Advise parents if the ultrasound is abnormal, the general paediatric team will arrange a clinic follow up.

Bibliography

  1. Bonadio W, Maida G. UTI in outpatient febrile infants younger than 30 days of age: a 10-year evaluation. Pediatr Infect Dis J. 2014;33(4):342
  2. AMH Children’s Dosing Companion (2015) Australian Medicines Handbook Pty Ltd
  3. WA Health Child and Adolescent Health Service. Department of General Paediatrics. Urinary Tract Infections: Investigation and Follow Up Clinical Practice Guideline. Version 1: 2015.
  4. Ismaili K, Lolin K, Damry N, Alexander M, Lepage P, Hall M J. Febrile UTIs in 0- to 3-month-old infants: a prospective follow-up study. Pediatr. 2011;158(1):91. 

Endorsed by:  Director, Emergency Department  Date:  Jun 2017


 Review date:   Apr 2020


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