Urinary tract infection - Pediatrics

Question 1

Types of UTI

Answer 1

• If UTI in the bladder only → cystitis (usually without fever)
• If UTI involves the kidney → pyelonephritis (usually with high fever)
• Septicaemia
• Asymptomatic bacteriuria.

Question 2

Etiology of UTI

Answer 2

• UTIs are caused mainly by colonic bacteria.
• In girls, 80% of all infections are caused by Escherichia coli, followed by Klebsiella, Pseudomonas, and Proteus spp.
• In boys <1 yr. of age, → Proteus, E. coli and gram-ve organisms are common.
• Staphylococcus saprophyticus and enterococcus are pathogens in both sexes
• Viral infection is rare but can occur (adenoviruses and enteroviruses)
• Mixed infection can occur.

Question 3

Risk factors of UTI

Answer 3

▪ Uncircumcised male
▪ Tight clothing (underwear)
▪ Female gender
▪ Pinworm infestation
▪ Vesicoureteral reflux
▪ Constipation
▪ Toilet training
▪ Anatomic abnormality (labial adhesion)
▪ Obstructive uropathy
▪ Neuropathic bladder
▪ Urethral instrumentation
▪ Wiping from back to front in girls

Question 4

Clinical picture of UTI

Answer 4

1. Asymptomatic bacteriuria: - positive urine culture without manifestations
2. New-born: -Sepsis
3. Infant: fever, irritability, screaming during micturition and may be associated with vomiting and poor feeding.
4. Child:
   o Specific urinary symptoms:
   -Pain with urination (dysuria)
   -Urinary frequency (needing to urinate frequently),
   -Urinary urgency (feeling a compelling urge to urinate)
   -Suprapubic tenderness.
   -Gross haematuria
   -Secondary enuresis.
   o Non-specific symptoms:
   -Fever (especially >39 c) usually
   -with upper UTI.
   -Abdominal pain (loin pain).
   -Vomiting.

Question 5

Diagnosis of UTI

Answer 5

• Urine analysis: depends on proper sampling
  o Toilet trained children by taking mid-stream clean catch.
  o Non-toilet trained children by catheterization or suprapubic aspiration.
  o Presence of WBC (pyuria) and bacteria suggests UTI
  o Presence of nitrites and leucocyte esterase +ve are more suggestive for UTI
• A urine culture is necessary for confirmation and appropriate therapy → Positive result if > 100.000 colonies of a single pathogen in clean
  catch sample or > 10.000 urinary catheter sample or any colony count from supra pubic aspirate.
• If < 10.000 colonies → suggest contaminations if clean catch or catheter
  samples.
• If child seriously unwell, measure serum electrolytes, CBC, CRP and ESR.
• Renal imaging → abdominal sonar, voiding cystourethrography and DMSA renal scan may be indicated in:
  o Atypical UTI (sepsis, abdominal mass, poor urine flow, raised creatinine, infection with organism other than E coli …..)
  o Recurrent UTI (≥ 2 times in 6 months or ≥ 4 times in 1year)

Question 6

Treatment of UTI

Answer 6

• Symptomatic treatment for fever and vomiting and adequate hydration.
• Antibiotic therapy:
  -Oral antibiotics:
  o Used in acute uncomplicated UTI (cystitis: 7 days) & (pyelonephritis:10 days).
  o Type of oral antibiotics: oral 3rd generation cephalosporin or amoxicillin or nitrofurantoin (used for prophylaxis). If allergy is
  present to any one → oral trimethoprim-sulphamethoxazole.
  -IV antibiotics: better combined antibiotics in a hospital (gentamycin or cefotaxime plus amoxicillin (for enterococci)) for 10-14 days are
  indicated in:
  1. Sepsis or infants < 3 month (fear of sepsis)
  2. Acute kidney injury
  3. Poor hydration
  4. Failure of outpatient treatment
  5. Renal abscess
• Urology consultation if structural abnormality, abscess, or dysfunctional elimination.
  ➢ Prevention: - for recurrent UTI:
• Remove underlying risk factors
• Adequate hydration and bladder emptying every 3-4 hours
• Probiotic therapy: improve urogenital flora
• Cranberry juice: prevents bacterial adhesion and biofilm formation.
• UTI prophylaxis: low dose cotrimoxazole or nitrofurantoin for 6 months (controversial).