Urinary Tract Infection (UTI Children)

ℹ️ About

• 🧒 Urinary Tract Infection (UTI) in Children
• 👧 Affects ~3% of girls and 👦 ~1% of boys before age 11
• 🔁 Can recur and, if untreated, may contribute to renal scarring → hypertension in later life

🧬 Aetiology (Structural abnormalities in ~50%)

• 🚹 Posterior urethral valves → bilateral hydronephrosis (boys)
• 🔄 Pelviureteric junction obstruction → unilateral hydronephrosis
• 🚧 Vesicoureteric junction obstruction → unilateral hydronephrosis
• 🪥 Affected kidneys may be small and dysplastic

🔗 Associated Causes

• 🚽 Poor bladder emptying (neurogenic bladder, poor voiding habits)
• 👧 Vulvitis or rushing micturition → incomplete voiding
• 💩 Constipation & loaded rectum compress bladder outlet
• 🔁 Vesicoureteric reflux (VUR) – abnormal ureteric entry into bladder → retrograde flow

🦠 Common Organisms

• 🟢 E. coli (most common)
• 🟡 Proteus (more common in boys; associated with stones)
• 🔵 Pseudomonas (often in children with structural urinary anomalies or instrumentation)

🩺 Clinical Features

• 🌡️ Fever, dysuria, frequency, lethargy
• 🤢 Vomiting, poor feeding, failure to thrive, septicaemia
• 🍼 Neonates: jaundice, irritability
• ⚡ Febrile convulsions (sometimes first presentation)
• 🪙 Abdominal/loin pain, secondary enuresis (bedwetting)

🔎 Investigations

• 🖥️ Ultrasound (USS): hydronephrosis, renal size, cysts
• 🧪 Urine sample: – Preferred: clean catch or suprapubic aspiration – Test: dipstick (nitrites, leukocyte esterase, protein) + microscopy/culture
• 💡 In recurrent/atypical cases: consider MCUG (micturating cystourethrogram) to check for reflux

💊 Management

• 💧 Ensure hydration + address constipation (reduce recurrence risk)
• 💊 Oral antibiotics: most UTIs resolve within 24–48h with prompt treatment
• 🏥 Admit if: – Age <3 months – Toxic/septic child – Vomiting/poor oral intake – Severe/recurrent infections – Give IV antibiotics (e.g. IV cefotaxime/ceftriaxone)
• 📅 Follow-up: renal imaging if atypical/recurrent UTI or abnormal exam findings

📚 References

• NICE CKS: UTI in Children
• NHS: UTIs in Children

💊 Case Reports

• 🍼 Case 1 – Age 6 months (Febrile UTI): Infant presented with fever, irritability, and poor feeding. No localising features. Urine obtained via catheter showed leukocytes and nitrites; culture grew E. coli. Diagnosis: First febrile urinary tract infection. Management: IV cefotaxime switched to oral antibiotics after 48 hours; renal ultrasound arranged to rule out structural anomalies. Teaching point: In infants under 12 months, fever without focus should always prompt urine testing — early imaging is important to detect vesicoureteric reflux or obstruction.
• 👧 Case 2 – Age 5 years (Lower UTI): Girl complained of dysuria, frequency, and suprapubic pain, but was otherwise well. No fever or flank pain. Urine dip positive for nitrites and leukocytes. Diagnosis: Uncomplicated lower UTI (cystitis). Management: Oral trimethoprim for 3 days, increased fluid intake, and hygiene advice (avoid bubble baths, front-to-back wiping). Teaching point: Older toilet-trained girls are prone to cystitis due to short urethra and poor hygiene — treatment is short-course oral antibiotics without imaging unless recurrent.
• 🧒 Case 3 – Age 9 (Recurrent UTI with Vesicoureteric Reflux): Boy with repeated episodes of fever and flank pain. Ultrasound showed mild hydronephrosis; micturating cystourethrogram (MCUG) confirmed grade II vesicoureteric reflux. Diagnosis: Recurrent febrile UTIs secondary to VUR. Management: Low-dose prophylactic trimethoprim, regular follow-up, and renal function monitoring. Teaching point: Recurrent febrile UTIs in older children warrant imaging for reflux or obstruction — early recognition prevents renal scarring and long-term hypertension.