Chapter 1
Urinary Tract Infection: USA
Angela M. Arlen and Christopher S. Cooper
Key Points
››UTI must be suspected in febrile infants.
››Catheterized or suprapubic urine specimens are superior, but mid-stream clean catch samples can be obtained in toilet-trained children.
››Routine follow-up culture is not necessary if organism is sensitive to originally selected antibiotic.
››Neurogenic bladders that are frequently instrumented will have colonization; urine culture should be obtained only if child is symptomatic.
››Evaluation of febrile UTI includes renal US and VCUG.
1.1 Introduction
Diagnosis, treatment and management of urinary tract infections in the pediatric population remain controversial. Pediatric UTIs are common and constitute a significant health burden; it is estimated that 7% of girls and 2% of boys under age 6 will be diagnosed with a urinary tract infection. In addition to appropriate treatment, the goal of managing UTIs in children should be to identify and modify factors that may affect renal parenchyma and function.
P.P. Godbole et al. (eds.), Guide to Pediatric Urology and |
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Surgery in Clinical Practice, DOI: 10.1007/978-1-84996-366-4_1,
© Springer-Verlag London Limited 2011
4 A.M. Arlen and C.S. Cooper
1.2 Risk Factors
1.Age: prevalence of bacteruria is higher in first year of life than other times during childhood.
2.Race:Caucasians are more likely than Hispanic orAfricanAmerican children to develop UTI.
3.Uncircumcised foreskin in males 6 months of age or younger increases the incidence of urinary tract infection ten times compared to circumcised males.
4.Incomplete bladder emptying or infrequent voiding: stasis allows growth of bacteria that would normally be flushed out with voiding.
5.Difficulty relaxing pelvic floor during voiding.
6.Constipation/encopresis: approximately 1/3 of children with recurrent UTIs have associated bowel problems.
7.Neurogenic bladder (managed with catheterization):
•Bacteruria and pyuria occur in most children.
•E. coli strains in this population commonly reflect colonization.
1.3 Presentation
1.Infants: in febrile infants, a urine specimen must be obtained even if signs point elsewhere; UTI accounts for 4.1–7.5% pediatric fevers
2.Young children (<2 years): fever, irritability, poor appetite, vomiting and diarrhea
3.Older children: dysuria, suprapubic pain, urgency, frequency, incontinence and abdominal/flank pain
1.4 Diagnosis
1.Examination of urine:
•Infants and young children: a catheterized specimen should be obtained.
•Toilet-trained children: a mid-stream, clean-catch urine specimen can be obtained but contamination can be difficult to rule out.
Chapter 1. Urinary Tract Infection: USA |
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•A bagged specimen is only useful if negative; if positive, a catheterized specimen should be obtained. Bagged urine specimens are unreliable and unacceptable for diagnosis of UTI in high-risk population and infants younger than 2 months.
•Positive leukocyte esterase or nitrite with five or more white blood cells and presence of bacteria on microscopy is highly predictive of infection.
2.Urine cultures with greater than 105 colony-forming units are considered positive; however, if the urine is obtained in a sterile fashion, fewer colony-forming units can constitute an infection.
1.5 Common Pathogens
1.Escherichia coli (54–67%)
2.Klebsiella (6–17%)
3.Proteus (5–12%)
4.Enterococcus (3–9%)
5.Pseudomonas (2–6%)
1.6 Treatment
1.Infants younger than 90 days:
•Consider IV antibiotics (ampicillin and gentamicin vs. third generation cephalosporin), especially with infants 30 days and younger.
•Need for admission depends on clinical status.
2.Young children (<2 years):
•Outpatient therapy with parenteral third generation cephalosporin (once daily).
•If less ill and capable of taking oral fluids, treat with 7–10 days of antimicrobials with broad genitourinary pathogen coverage.
•No follow-up culture is required if organisms are sensitive to selected antibiotic.
6 A.M. Arlen and C.S. Cooper
3.Older children:if uncomplicated UTI,oral broad-spectrum antimicrobial agents are well-tolerated and clear the infection after a 3–5 day course if there is no known genitourinary pathology.
1.7 Imaging
All children with culture-documented UTI and fever greater than 38.5°C should have follow-up imaging to determine any anatomic anomalies.
1.Retroperitoneal ultrasound: should include evaluation of kidneys and bladder and can be obtained at any time after the infection
•Children younger than 5 years of age with febrile UTI.
•Males of any age with first UTI.
•Females younger than 2 years of age with first UTI.
•Children with recurrent UTIs.
2.Voiding cystourethrogram (VCUG): should be obtained after confirmation that infection has cleared
•Children younger than 5 years of age after febrile UTI.
•Males of any age after first UTI.
•Females younger than 2 years of age with first UTI.
•Children with recurrent urinary tract infections.
3.DMSA renal scan: differentiate true pyelonephritis and severity of infections
•Useful in high risk patients for prognostic purposes.
•Renal scarring is a risk factor for future scarring.
1.8 Indications for Referral
1.Febrile UTI in infant
2.UTI + anatomic anomaly on US or VCUG
3.Recurrent urinary tract infections
4.Voiding dysfunction unresponsive to timed voiding and bowel regimen