Urinary Tract Infections
Dennis Scolnik
Introduction
Urinary tract infections (UTIs) occur frequently throughout childhood
Prevalence in first year of life: 6.5% (girls), 3.3% (boys)
Prevalence in children: 8.1% (girls), 1.9% (boys)
Rate of UTIs is 5-20 × higher in uncircumcised boys
Less common in African American children
Prevalence in febrile children 2 months to 2 years of age: ˜ 5%
Upper respiratory tract infection or otitis media does not preclude UTI
Other risk factors: fever > 24 hours, fever > 38.9°C and prior UTIs
Clinical Presentation
Different presentations through childhood:
Infants
Nonspecific feeding difficulty, anorexia, irritability, vomiting, diarrhea
2/3 have fever, few present with sepsis syndrome or shock
Late onset jaundice, with elevation of both direct and indirect bilirubin may be the only indication of infantile UTI
Toddlers and Preschool Children
Nonspecific presentation
May notice a change in urine smell, color, or pattern of urination
Schoolchildren
More likely to present with “classic” adult symptoms and signs
Frequency, dysuria, and urgency are common but not pathognomonic
May report changed behavior, vomiting, anorexia, fever, abdominal pain, or secondary enuresis
If untreated, symptoms may subside over 1-3 weeks, although the urine culture remains positive
In recurrent UTIs, symptoms may be minimal
UTI vs Pyelonephritis
Not possible to clinically distinguish lower UTIs from pyelonephritis in young children; therefore must maintain a high index of suspicion
75% of children < 5 years with febrile UTIs have upper tract involvement
Costovertebral angle tenderness, rigors, and toxicity suggest upper tract involvement
Up to 50% of children with febrile UTIs develop renal scarring—may be associated with development of hypertension and end stage renal disease
Most scars develop in first five years of initial diagnosis
When to Send a Urine Culture?
Febrile infants < 1 year
Symptoms/signs suggestive of UTI
Toxic/septic/shock without obvious cause
History of recurrent UTI, regular catheterization, or known urinary tract anomaly
Unexplained fever or symptoms
Obtaining a Urine Sample
Four methods: midstream/clean catch sample, urine bag, catheterization, and suprapubic aspiration
Urine must be promptly analyzed and plated
Refrigerate specimen if > 30-min delay between collection and plating
Midstream/Clean Catch Sample
Least traumatic method
Can be used in all children without obvious infection or anomaly of external genitalia
In infants the parent may prefer to wait with a sterile container and catch urine
Catheterization
Method of choice for febrile infants, toxic/septic/shock, and in all age groups with an urgent clinical indication to start antibiotic treatment
Genitalia must be carefully cleansed and strict aseptic technique followed to avoid iatrogenic infection
Contraindications: gross infection of genital area, labial adhesions, and uncircumcised boys whose urethral opening cannot be visualized
Foreskin should not be forcibly retracted as predisposes to paraphimosis
