3. Definition
• Urine tract infection is colonisation by bacteria
in any part of the urinary tract
• It is a common bacterial infection in children
• Associated with high morbidity
4. Rationale for studying UTI in children
• UTIs have been considered a risk factor for the
development of renal insufficiency or end-
stage renal disease in children
• Many children receive antibiotics for fever
without a focus resulting in a partially treated
UTI.
5. Epidemiology
• Occur in 1-3% of girls and 1% of boys.
• In girls it peaks during infancy and toilet
training.
• The prevalence varies with age.
• During the 1st yr of life, male : female ratio is
2.8-5.4 : 1.
• Beyond 1-2 yr, there is a female
preponderance, with a male : female ratio of
1 : 10.
6. Etiology
• Route of Infection
• Hematogenous spread (neonates)
• Ascension of bacteria migrating from GI tract (beyond infancy)
Pathogens
Gr – Bacilli
(90%)
Gr - Cocci Gr + Cocci
(5%)
Fungi Viruses Parasites Other
E. Coli (80%)
Klebsiella
Enterobacter
Citrobacter
Proteus Pseudomonas
Morganella
Providencia
Serratia
Neisseria Enterococcus
Staphylocccus
Streptococcus
Candida
Trichosporon
Microsporidia
Adenovirus
Polyomavirus
HSV
Schistosoma Chlamydia
Mycobacteria
*in children < 2yrs, difficult to distinguish between upper and lower UTI
7. Forms of UTIs
• Pyelonephritis
• Cystitis
• Asymptomatic bacteriuria
8. Risk factors for developing UTI
• Infants
• Uncircumcised boys ( there is a 4-10 fold increase in risk of
infection< though most don’t develop uti)
• Any obstruction in the urine tract
• Bladder catheterisation
• Family history of VUR or renal disease
• Constipation
• Evidence of spinal lesions
• Immunodeficiency
• Toilet training
• Wiping from back to front in girls
• Sexual activity (particularly in females)
9. Pyelonephritis
• Refers to infection of the upper urinary tract
• It is characterized by any or all of the following:
abdominal, back, or flank pain; fever; malaise;
nausea; vomiting; and, occasionally, diarrhea.
• Fever may be the only manifestation.
• Newborns present with non specific symptoms
such as poor feeding,fever, irritability, jaundice,
and weight loss.
10. Cystitis
• Infection of the bladder
• Symptoms include dysuria, urgency, frequency, suprapubic
pain, incontinence, and malodorous urine.
• Cystitis does not cause fever and does not result in renal
injury.
• Acute hemorrhagic cystitis often is caused by E. coli, or
adenovirus.
• Adenovirus cystitis is more common in boys; it is self-
limiting, with hematuria lasting approximately 4 days.
11. Asymptomatic bacteriuria
• Refers to a condition in which there is a positive urine
culture without any manifestations of infection.
• It is most common in girls.
• The incidence declines with increasing age.
• This condition is benign and does not cause renal
injury, except in pregnant women, in whom if left
untreated, can result in a symptomatic UTI.
12. Pathogenesis of UTI
• Most UTIs are ascending infections.
• The bacteria arise from the fecal flora, colonize the perineum, and
enter the bladder via the urethra.
• In uncircumcised boys, the bacterial pathogens arise from the flora
beneath the prepuce.
• In some cases, the bacteria causing cystitis ascend to the kidney to
cause pyelonephritis through reflux of infected urine leading
immunologic and inflammatory response, and later renal scarring.
• Rarely, renal infection occurs by hematogenous spread, as in
neonates.
13. Diagnosis
• Urine culture
• >100,000 colonies of a single pathogen, or if there are 10,000 colonies
plus symptoms, consider UTI
• Ways to obtain a urine sample
– In toilet-trained children, a midstream urine sample usually is satisfactory;
clean the introitus before obtaining the specimen.
– In uncircumcised boys, the prepuce must be retracted
– In children who are not toilet trained, a catheterized urine sample should be
obtained
– Alternatively, the application of an adhesive, sealed, sterile collection bag after
disinfection of the skin of the genitals
14. Other supportive investigations
• Leukocytosis, neutrophilia, and elevated serum erythrocyte
sedimentation rate and C-reactive protein.
• These are not specific for UTI
• Nitrites and leukocyte esterase usually are positive in infected
urine.
• Renal scan is performed to assess kidney size, detect
hydronephrosis and ureteral dilation, identify the duplicated urinary
tract, and evaluate bladder anatomy
• Technetium-labeled dimercaptosuccinic acid (DMSA) renal scan to
assess for renal scarring.
15. Treatment
• Goals
– Relieve acute symptoms
– Eliminate infection and prevent urosepsis
– Prevent recurrence and long-term complications
16. Treatment
• Cystitis
– 5-day course of therapy with trimethoprim-
sulfamethoxazole or trimethoprim
– Effective against E. coli.
– Nitrofurantoin 5-7 mg/kg/24 hr in divided doses is
effective against Klebsiella and Enterobacter
organisms.
– Amoxicillin (50 mg/kg/24 hr) also is effective as
initial treatment but has no clear advantages over
sulfonamides or nitrofurantoin.
17. Treatment-Pyelonephritis
• Broad spectrum antibiotics for 10- to 14-days eg cefixime, oral
fluoroquinolone such as ciprofloxacin
• Indications for admission
• Children with dehydrated, vomiting, unable to drink fluids, children
≤1mo of age.
• Parenteral treatment with ceftriaxone 50-75 mg/kg/24 hr, or
cefotaxime 100 mg/kg/24 hr, or ampicillin 100 mg/kg/24 hr with
an aminoglycoside such as gentamicin 3-5 mg/kg/24 hr
• Treat the underlying cause of the UTI
18. Prognosis
• Very good with early intervention
• Recurrent UTI is associated with increased risk
of development of end stage renal disease.