Paediatric Urinary Tract Infection (UTI)
Lesson Objectives
By the end of this lesson, learners should be able to:
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Define urinary tract infection (UTI) and differentiate between cystitis and pyelonephritis.
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Identify the common causative organisms of UTI in children.
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Recognize age-specific clinical presentations of UTI.
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Interpret urinalysis, urine microscopy, and urine culture results.
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Outline empiric and definitive treatment regimens, including oral and IV antibiotics.
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Understand specimen collection methods appropriate for age and toilet-training status.
Description
Urinary tract infections occur when bacteria ascend the urinary tract, typically starting at the urethra and moving to the bladder (cystitis) or further to the ureters and kidneys (pyelonephritis). Infants often present late with nonspecific symptoms such as fever, while older children can localize urinary discomfort earlier in the course of infection.
Common causative organisms:
| Organism | Percentage of UTIs in Children |
|---|---|
| Escherichia coli | 54–67% |
| Klebsiella | 6–7% |
| Proteus | 5–12% |
| Enterococcus | 3–5% |
| Pseudomonas | 2–6% |
Clinical Features
| Age Group | Symptoms |
|---|---|
| Infants / Young children | Fever, irritability, vomiting, poor feeding |
| Older children | Dysuria, urinary frequency, suprapubic discomfort, flank pain, costovertebral pain, abdominal pain |
Investigations
| Test | Key Points |
|---|---|
| Urinalysis | Positive nitrite suggests UTI; leukocyte esterase indicates pyuria; false negatives may occur |
| Urine microscopy | ≥10 WBC/μL in uncentrifuged specimen is significant |
| Urine culture | For non-toilet trained children, use urethral catheterization or suprapubic aspiration; for toilet-trained children, use midstream urine sample |
Treatment
Empiric therapy:
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Start with quinolones or other empiric antibiotics depending on local resistance patterns.
Definitive therapy:
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Adjust treatment based on culture results.
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Oral antibiotics: 10–14 days.
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IV antibiotics: 3 days initially, then switch to oral antibiotics to complete 10-day course.
⚠️ Prompt treatment is important to prevent renal scarring and long-term complications.
Key Summary
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UTIs result from bacterial invasion of the urinary tract, often starting in the urethra and bladder.
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E. coli is the most common pathogen.
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Clinical presentation varies by age; infants may present with nonspecific fever, while older children report urinary symptoms.
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Urinalysis, microscopy, and culture are essential for diagnosis.
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Start empiric antibiotics, then adjust according to culture results.
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Ensure proper urine collection techniques based on age and toilet training.