Urinary Tract Infections in Children
Urinary Tract Infections in Children
Introduction
Urinary tract infections (UTIs) are common bacterial infections in pediatric populations, requiring prompt recognition and appropriate management to prevent complications and long-term sequelae.
Key Points
- Second most common bacterial infection in children after respiratory infections
- Risk of renal scarring highest in children under 2 years
- Presents differently in various age groups
- Requires age-appropriate diagnostic approach
- May indicate underlying urological abnormalities
Epidemiology & Risk Factors
Prevalence by Age and Gender
- First Year of Life:
- Males: 2.7%
- Females: 0.7%
- Higher in uncircumcised males under 3 months
- School Age:
- Females: 3-5%
- Males: 1%
Risk Factors
- Anatomical:
- Vesicoureteral reflux (VUR)
- Posterior urethral valves
- Neurogenic bladder
- Labial adhesions in females
- Functional:
- Constipation
- Voiding dysfunction
- Poor bladder emptying
- Other:
- Previous UTIs
- Family history of VUR or UTIs
- Uncircumcised male infants
- Immunocompromised status
Pathophysiology
Route of Infection
- Ascending Infection:
- Most common route
- Bacteria from perineal area ascend via urethra
- Enhanced by anatomical or functional abnormalities
- Hematogenous Spread:
- Rare in immunocompetent children
- More common in neonates
Common Pathogens
- Gram-negative organisms:
- Escherichia coli (80-90%)
- Klebsiella species
- Proteus mirabilis (more common in males)
- Pseudomonas aeruginosa
- Gram-positive organisms:
- Enterococcus species
- Staphylococcus saprophyticus (adolescents)
Host Defense Mechanisms
- Anatomical barriers
- Urine flow
- Urinary pH
- Immunological factors
Clinical Presentation
Age-Specific Presentations
- Neonates (0-28 days):
- Poor feeding
- Lethargy
- Temperature instability
- Jaundice
- Sepsis-like picture
- Infants (1-24 months):
- Fever without source
- Irritability
- Vomiting
- Poor feeding
- Failure to thrive
- Older Children:
- Frequency
- Urgency
- Dysuria
- Abdominal/flank pain
- Secondary enuresis
Signs of Upper vs Lower UTI
- Upper UTI (Pyelonephritis):
- High fever (≥38.5°C)
- Flank pain/tenderness
- Vomiting
- Systemic symptoms
- Lower UTI (Cystitis):
- Dysuria
- Frequency
- Urgency
- Suprapubic pain
Diagnostic Approach
Urine Collection Methods
- Suprapubic Aspiration:
- Gold standard
- Any growth significant
- Used in neonates
- Catheterization:
- Preferred method in infants
- ≥50,000 CFU/mL significant
- Clean Catch:
- For toilet-trained children
- ≥100,000 CFU/mL significant
- Bag Specimen:
- High false-positive rate
- Not recommended for diagnosis
- Negative result may rule out UTI
Laboratory Studies
- Urinalysis:
- Leukocyte esterase
- Nitrites
- Microscopy (>5 WBC/HPF)
- Urine Culture:
- Gold standard for diagnosis
- Collection method determines significance
- Antibiotic sensitivity crucial
- Blood Tests:
- Complete blood count
- C-reactive protein
- Blood culture in febrile infants
Imaging Studies
- Renal/Bladder Ultrasound:
- First-line imaging
- Evaluates anatomy and complications
- Recommended for all febrile UTIs in infants
- Voiding Cystourethrogram (VCUG):
- Diagnoses vesicoureteral reflux
- Indicated in specific scenarios
- Timing controversial
- DMSA Scan:
- Identifies renal scarring
- Used in research settings
- May guide long-term management
Treatment Approaches
Initial Management
- Empiric Antibiotics:
- Based on local resistance patterns
- Age-appropriate choices
- Route depends on severity
- Supportive Care:
- Hydration
- Fever control
- Pain management
Antibiotic Selection
- Oral Options:
- Trimethoprim-sulfamethoxazole
- Amoxicillin-clavulanate
- Cephalosporins
- Nitrofurantoin (lower UTI only)
- Parenteral Options:
- Gentamicin
- Ceftriaxone
- Ampicillin + Gentamicin (neonates)
Duration of Therapy
- Pyelonephritis: 7-14 days
- Cystitis: 3-5 days
- Complicated UTI: 10-14 days
Prevention & Follow-up
Preventive Measures
- Behavioral Modifications:
- Regular voiding
- Proper wiping technique
- Adequate fluid intake
- Treatment of constipation
- Antibiotic Prophylaxis:
- Selected cases only
- Based on risk factors
- Regular monitoring required
Follow-up Care
- Monitoring:
- Clinical response
- Repeat urine cultures
- Imaging follow-up
- Long-term Considerations:
- Growth monitoring
- Blood pressure checks
- Renal function assessment
Special Considerations
High-Risk Groups
- Neonates and young infants
- Children with urological abnormalities
- Immunocompromised patients
- Recurrent UTI cases
Complications
- Acute:
- Renal abscess
- Sepsis
- Acute kidney injury
- Chronic:
- Renal scarring
- Hypertension
- Chronic kidney disease
Video Notes with Music
Urinary Tract Infections: Objective QnA
- What is the definition of a urinary tract infection (UTI)?
The presence of bacteria in the urine along with symptoms of infection - What is the most common causative organism for UTIs in children?
Escherichia coli (E. coli) - What are the classic symptoms of UTI in older children?
Dysuria, frequency, urgency, and sometimes abdominal or flank pain - How do UTI symptoms differ in infants and young children?
Often non-specific: fever, irritability, poor feeding, vomiting - What is the gold standard for diagnosing UTI in children?
Urine culture from a properly collected specimen - What is the recommended method for urine collection in non-toilet-trained children?
Catheterization or suprapubic aspiration - What is the significance of pyuria in diagnosing UTI?
Presence of white blood cells in urine suggests inflammation, supporting UTI diagnosis - What is the typical duration of antibiotic treatment for uncomplicated UTI in children?
7-14 days - What imaging is recommended after a first febrile UTI in children?
Renal and bladder ultrasound - What is the role of voiding cystourethrogram (VCUG) in evaluating children with UTI?
To diagnose vesicoureteral reflux - What percentage of children with a febrile UTI have vesicoureteral reflux?
Approximately 30-40% - What is the significance of recurrent UTIs in children?
May indicate underlying anatomical abnormalities or voiding dysfunction - How does circumcision status affect UTI risk in male infants?
Uncircumcised males have a higher risk of UTI in the first year of life - What is the role of antibiotic prophylaxis in preventing recurrent UTIs?
May be considered in children with high-grade vesicoureteral reflux or recurrent infections - How does constipation contribute to UTI risk in children?
Can lead to incomplete bladder emptying and increased bacterial colonization - What is the concept of asymptomatic bacteriuria?
Presence of bacteria in the urine without symptoms, generally not requiring treatment in children - How does neurogenic bladder increase UTI risk?
Incomplete bladder emptying and catheterization increase bacterial colonization - What is the role of probiotics in preventing UTIs in children?
May help prevent recurrent UTIs, but more research is needed - How do anatomical abnormalities like posterior urethral valves contribute to UTI risk?
Cause urinary stasis and incomplete bladder emptying, increasing bacterial colonization - What is the significance of renal scarring in children with UTIs?
Can lead to hypertension and chronic kidney disease in the long term - How does vesicoureteral reflux contribute to the risk of pyelonephritis?
Allows backflow of infected urine to the kidneys, increasing risk of upper tract infection - What is the role of DMSA scan in evaluating UTIs in children?
To detect acute pyelonephritis and assess for renal scarring - How does proper wiping technique (front to back) in girls help prevent UTIs?
Reduces the risk of introducing fecal bacteria into the urethral area - What is the significance of urine biomarkers in diagnosing UTIs?
Emerging tools for rapid, accurate diagnosis without waiting for culture results - How does bladder and bowel dysfunction (BBD) relate to UTIs in children?
BBD can increase the risk of UTIs due to incomplete bladder emptying and constipation - What is the concept of "breakthrough" UTIs?
Infections that occur despite antibiotic prophylaxis - How does diabetes mellitus affect UTI risk in children?
Increases risk due to glucosuria and impaired immune function - What is the role of cranberry products in preventing UTIs in children?
May help prevent recurrent UTIs, but evidence is limited - How does clean intermittent catheterization affect UTI risk in children with neurogenic bladder?
While necessary for bladder management, it increases the risk of introducing bacteria - What is the significance of nitrite-positive urine in diagnosing UTIs?
Suggests the presence of nitrate-reducing bacteria, supporting UTI diagnosis
Further Reading
- Diagnosis and Treatment of Urinary Tract Infections in Children (American Family Physician)
- NICE Guidelines: Urinary tract infection in under 16s: diagnosis and management
- UpToDate: Urinary tract infections in children: Epidemiology and risk factors
- Urinary Tract Infections in Children: EAU/ESPU Guidelines (European Urology)
