Pediatric UTI

Screen UTI

• <3 years old, if fever with unclear source
• >3 years old, consider testing if presence of dysuria, urinary frequency, hematuria, abdominal/back pain, daytime incontinence
  • Consider low risk UTI (<1%) if female and no more than one of following
    • <1 years old
    • White race
    • T>39° C
    • Fever >2d
    • Absence of source

Symptoms

• Lower urinary tract (cystitis)
  • Dysuria, frequency, urgency, malodorous urine, enuresis, hematuria, suprapubic pain
• Upper urinary tract (pyelonephritis)
  • Fever, chills, CVA pain/tenderness
  • Infants may have non-specific signs (poor appetite, failure to thrive, lethargy, irritability, vomiting, diarrhea)

Urinalysis and Urine Culture

• Catheterization or mid-stream if toilet trained for culture
  • May consider 25 mins after feeding, holding baby upright, tap on bladder x30s then massage sacrum x30s (repeat maneuvers until micturition)
• May consider bag urine to screen by microscopy (positive if >10-20 WBC/hpf, or LE, NT positive) then catheterization needed
• Criteria for UTI
  • Positive urine specimen from suprapubic bladder puncture
  • >1000 cfu/mL from bladder catheterisation
  • >10^4 with symptoms or >10^5 without symptoms from midstream void
• Sterile pyuria may be due to incomplete antibiotic treatment, urolithiasis, foreign body, infection by Mycobacterium tuberculosis, Chlamydia trachomatis
• Negative nitrites not reliable if infant empties bladder frequently (requires 4h to convert)

Treatment (usually 7-14d)

• Ampicillin 50 mg/kg/dose IV q6h + Gentamicin 7.5 mg/kg IV/IM once daily
• Cefixime 8mg/kg PO daily (max 400mg/d)
• TMP/SMX 6-12mg/kg/day divided q12h (max 320mg TMP daily), avoid in newborns
• Amox/Clav 7:1 suspension, 45mg/kg/day of Amox divided q8h (max 3g Amox daily)
• Alternatives
  • Amoxicillin 50 mg/kg/day divided q8h (max 3g daily)
  • Cephalexin 50 mg/kg/day divided q6h (max 500mg/dose)

Disposition

• Admit if <2 months old or complicated
• Consider discharge if well and >2 months old with follow-up

Imaging

• Renal-Bladder Ultrasound if child
  • <2yo with first febrile UTI within 2w of acute illness
  • Recurrent UTIs
  • Pyelonephritis (Complicated)
  • Family/personal history of urologic/renal abnormalities
• VCUG if
  • Hydronephrosis on ultrasound that suggests high grade (4-5) VUR, in addition consult urology or nephrology
  • <2yo with second febrile UTI

Prevention

• Prophylaxis not routinely recommended, but may consider in Grade IV/V VUR or significant urological anomaly