1. David Hunter & Kathryn Hassan

2. Summary
 Introduction
 Causes
 Symptoms & Signs
 Investigations
 Management
 Case Presentation

3. Introduction
 What is UTI?:
 A bacterial infection affecting
any part of the urinary tract:
○ Kidneys (pyelonephritis):
fever + systemic involvement
○ Cystitis: fever is low
grade/absent

4. Introduction
 Why is it important?:
 Pyelonephritis may damage the growing kidney
○ Forms a scar
○ Predisposes to hypertension & chronic renal failure
(if scarring is bilateral)
 Up to 50% of cases indicate underlying urinary
tract abnormality
 In the UK, 10-20 children each year enter end
stage renal failure programmes (due to reflux &
chronic pyelonephritis complications)

5. Causes - Bacteria
 Bacterial colonisation of any part of the
urinary tract
 Typical causative bacteria:
Organism Frequency (%)
E. Coli + other coliforms 68+
Proteus mirabilis 12
Staphylococcus
sacrophyticus/epidermidis
10
Enterococcus faecalis 6
Klebsiella aerogenes 4
Kumar and Clark: Kumar and Clark’s Clinical
Medicine 7E; p600

6. Bacterial Causes in
Children
 The top 3 are:
 E.coli
 Proteus:
○ Boys > Girls
○ Predisposes to phosphate stone formation
 Pseudomonas:
○ May indicate abnormality in urinary tract
affecting drainage

7. Incomplete Bladder
Emptying
 Contributing factors:
 Vesicoureteric reflux
 Infrequent voiding → bladder enlargement
 Vulvitis
 Neuropathic bladder
 Hurried micturition
 Obstruction eg. by a loaded rectum
(constipation)

8. Causes - Abnormalities
 Urinary tract abnormalities are a
predisposing factor
 It is important to screen for these
(particularly in male children)
 Vesicoureteric reflux
 70% of children <1 year with a UTI will have
this

9. Vesicoureteric reflux (VUR)
 Backflow of urine from the bladder into
the ureter
 Causes recurrent UTIs
 Can eventually lead to renal scarring

10. Why is it important?
 Return of urine from ureter to bladder
 Risk of kidney infection (pyelonephritis)
 Bladder voiding pressure transmitted to
renal papillae

11. Associations
 Familial
 30-50% chance of occuring in 1st° relatives
 Severe cases may be associated with
renal dysplasia

12. Vesicoureteric reflux
 Primary:
 Terminal portion of ureter is short
 Ureter at 90° angle to bladder mucosal surface
(rather than acute)
 Bladder contraction holds it open & causes reflux
of urine
 Secondary:
 Valvular mechanism intact, but becomes
overwhelmed by ↑ vesicular pressures caused by
obstruction
 May be secondary due to other bladder pathology

13. Vesicoureteric reflux
grading
 Grade I: reflux into non-
dilated ureter
 Grade II: reflux into renal
pelvis & calyces without
dilatation
 Grade III: mild/moderate
dilatation of ureter, renal
pelvis & calyces with
minimal blunting of fornices

14. Vesicoureteric reflux
grading
 Grade IV: dilation of renal
pelvis & calyces with
moderate ureteral
tortuosity
 Grade V: gross dilatation
of ureter, pelves &
calyces. Ureteral
tortuosity. Loss of
papillary impressions

15. Consequences
 Renal scarring
 Chronic renal failure if bilateral
 Risk of hypertension in childhood/early
adult life estimated at 10%

16. Presentation
 In infants, presentation may be non –
specific
 Symptoms/Signs:
 Lethargy/irritability
 Fever
 V & D
 Poor feeding/ failure to thrive
 Septicaemia
 Prolonged neonatal jaundice
 Febrile convulsions (only if >6 months old)

17. Protocol for Investigation

18. Who should be
investigated?
 Have a known antenatal renal anomaly
 Infants
 Boys
 More than one UTI
 Septicaemia
 Prolonged clinical course or fever >48
hours
 Family history of reflux
 Unusual organisms (not e.coli)

19. Collecting Urine
 Absorbent pads in nappy
 Clean-catch sample
 Adhesive plastic bag
 Suprapubic aspiration

20. Analysing the urine
 Culture and microscopy
○ >105 bacterial cell growth
○ Repeat samples
○ Mixed organisms suggests contamination
 Urine dipstick
○ White cells
○ Nitrates

21. Ultrasound
 Initial investigation of
choice
 Looks for
○ Serious structural
abnormalities and urinary
obstruction
○ Renal defects
 Subsequent investigations
depend on results of this

22. Further investigations
 Urethral obstruction
○ Micturating cystourethrogram (MCUG)
 Functional scans
○ 3-6 months after UTI
 MAG3
 DMSA
 IRC

23. Management
 Prompt treatment
 Oral antibiotics
○ Co-amoxiclav
 IV antibiotics if severely unwell
○ Cefotaxime or Amoxicillin
○ Gentamicin – monitor serum levels

24. Prevention
 High fluid intake
 Regular voiding
 Ensure complete bladder emptying
 Prevention or treatment of
constipation
 Good perineal hygiene
 Pro-biotics
○ Lactobacillus acidophilus
 Antibiotic prophylaxis
○ Trimethoprim – 2mg/kg at night

25. Follow up
 Urine culture
 Long term antibiotic
prophylaxis
○ Trimethoprim
 Circumcision
 Anti-reflux surgery
 Blood pressure monitoring
 Regular renal assessment

27. Case Study
 6-month old male - stopped feeding and
had a high intermittent fever. He was
referred to hospital where he had an
infection screen
 Urine examination
○ >100 white blood cells
○ >105 E.coli/ml

29. Case study
 He was treated with IV antibiotics
 Ultrasound scan showed a small right
kidney with a dilated renal pelvis and a
dilated ureter
 He was started on prophylactic
antibiotics

30. Case Study
 A DMSA scan performed 3 months later
confirmed bilateral renal scarring with
the right kidney only contributing to 17%
of renal function
 MCUG showed bilateral vesicoureteric
reflux

31. Case Study
 At 3 years of age the reflux has resolved
and antibiotic prophylaxis was stopped.
 His blood pressure and renal growth and
function continued to be monitored