approach to the management of UTI in pediatrics

1. Aseel Bzour, Pediatric resident

2. INTRODUCTION
Urinary tract infection (UTI) is a common and important clinical
problem in childhood.
Although children with pyelonephritis tend to present with fever, it is
difficult on clinical grounds to distinguish cystitis from
pyelonephritis, particularly in young children (< 2 years).
Upper UTIs (ie, acute pyelonephritis) may lead to renal scarring,
hypertension, and ESRD.

3. Prevalence:
In young children (< 2 years) with fever:
• The overall prevalence of UTI is approx 7 %
• It is highest among uncircumcised boys, particularly < 3 months.
• White children have a 2-4 fold higher prevalence than do black children.
• Girls have a 2-4 fold higher prevalence than do circumcised boys.
• White girls with a Temp ≥39°C have a UTI prevalence of 16%.
In older children: the prevalence of UTI was 7.8%.

4. MICROBIOLOGY:
Gram-negative bacterial pathogens
• E. coli is the most common bacterial cause of UTI (80 % of UTI).
• Others: Klebsiella, Proteus, Enterobacter, and Citrobacter.
• Infection with an organism other than E. coli is associated with a higher likelihood of renal scarring.
Gram-positive bacterial pathogens
• Staphylococcus saprophyticus, Enterococcus, rarely, S. aureus.
Viruses.
• are uncommon causes of UTI in children
• usually limited to the lower urinary tract
Fungi
• uncommon
• Risk factors: Immunosuppression and long-term use of broad-spectrum antibiotic, and indwelling urinary
catheter

5. PATHOGENESIS:
most UTI beyond the N.B period are the result of ascending
infection.
Colonization of the periurethral area by uropathogenic enteric
pathogens is the first step in the development of a UTI.
Pathogens attach to the uroepithelial cells via an active process
mediated by glycosphingolipid receptors on the surface of
epithelial cells. Bacterial attachment recruits toll-like receptors
(TLR). TLR binding triggers a cytokine response, which
generates a local inflammatory response.

6. PATHOGENESIS : VIRULENCE
FACTORS
A variety of virulence factors enable bacteria to ascend
into the bladder and kidney.
The best-studied virulence factors in E. coli are pili.
Bacteria possessing pili can adhere effectively to the
uroepithelium and ascend into the kidney, even in
children without VUR.
In the kidney, the bacterial inoculum generates an
intense inflammatory response, which may ultimately
lead to renal scarring.

7. • Age: highest in boys < 1 year and girls < 4 years.
• Lack of circumcision: 4-8 fold higher prevalence of UTI
• Female infants: 2-4 fold higher prevalence of UTI
• Race/ethnicity: white children > black children.
• Genetic factors
• Urinary obstruction:
• Anatomic conditions, Neurologic conditions, Functional conditions
• Suspect when: voiding problems, family hx of urologic abnormalities,
patient with GU abnormalities or when symptoms do not respond to
appropriate therapy.
• Bladder and bowel dysfunction
• Vesicoureteral reflux
• Sexual activity
• Bladder catheterization
HOST FACTORS:

8. BACTERIAL-HOST INTERACTIONS:
There is indirect evidence that alteration of the
normal periurethral flora promotes attachment
of pathogenic bacteria
Circumcision
Use of antibiotics

9. General risk factors:
• Recurrent febrile UTI
• Delay in treatment of acute
infection
• Bladder and bowel dysfunction
• UT Obstructive malformations:
• VUR
Predictors of renal scarring
after first UTI:
• VUR (high-grade)
• Abnormal renal bladder US
• Elevated inflammatory
markers: CRP of >40 mg/L or
PMNs >60 %
• Temperature ≥39°C
• organisms other than E. coli

11. UTI
Cystitis peylonephritis
Asymptomatic
bacteruria

12. Younger children
• nonspecific symptoms and signs
• History of UTI
• Temperature >40°C or > 24 hours
• Suprapubic tenderness
• Lack of circumcision
• Other symptoms: conjugated
hyperbilirubinemia, irritability, poor
feeding, or FTT
Older children:
• fever
• urinary symptoms
• abdominal pain
• fever, chills, flank pain
(pyelonephritis)
• short stature, poor weight gain, or
hypertension
• Suprapubic tenderness
• costovertebral angle tenderness

13. History Physical exam Investigations
Prompt recognition and treatment of UTI is an important factor in the
prevention of renal scarring.

14. Hx of acute illness
• fever
• urinary symptoms
• abdominal pain, suprapubic discomfort, back pain,
• vomiting
• recent illnesses, antibiotics administered
The PMHx should include risk factors for UTI:
• Chronic urinary symptoms
• Chronic constipation
• Previous UTI or previous undiagnosed febrile illnesses
• VUR
• Family hx of frequent UTI, VUR, and other genitourinary abnormalities
• Antenatally diagnosed renal abnormality
• chronic sequelae of UTI: Poor growth, Elevated blood pressure

15. Physical examination
VS: BP and Temp
Growth parameters:
poor weight gain, FTT
(chronic or recurrent
UTI)
Abdominal exam:
• suprapubic tenderness
• Abdominal mass (enlarged
bladder or enlarged kidney)
• costovertebral tenderness
Examination of the
external genitalia for
• anatomic abnormalities
• and signs of vulvovaginitis,
vaginal foreign body,
Evaluation of the
lower back for signs of
occult
myelomeningocele
Evaluation for other
sources of fever

16. LABORATORY EVALUATION
The laboratory evaluation for the child with suspected UTI
includes
obtaining a urine sample for
a dipstick and/or microscopic evaluation
and urine culture.
Pyuria and significant bacteriuria on urine culture are necessary
to make the diagnosis.

20. How to obtain
Catheterization
or suprapubic
aspiration is
the preferred
method of
urine collection
in infants and
young children
who are not
toilet-trained.
A clean-voided
specimen is the
preferred
method of
collection in
toilet-trained
children.
All urine
specimens
should be
examined as
soon as
possible after
collection.
Urine obtained
in a sterile
bag not be
used for
culture.

21. Dipstick analysis
• 88 % sensitive
• Leukocyte esterase: Positive result is
suggestive of UTI.
• Nitrite: positive test is suggestive of
UTI.
• highly specific, with a low false-
positive rate.
Microscopic exam
• Standard microscopy
• urine is examined for WBCs and
bacteria.
• Pyuria: ≥5 WBC/hpf
• Bacteriuria: presence of any
bacteria/hpf.
• sensitivity is at best 81 %,
• ●Enhanced urinalysis
• pyuria : ≥10 WBC/mm3
• Bacteriuria: any bacteria per 10 oil
immersion fields of a Gram-stained
smear.

22. Urine culture:
the standard test for the diagnosis of UTI.
should be performed for all children in whom UTI is a diagnostic consideration
Catheterization or suprapubic aspiration is the preferred in infants and children who are not toilet-
trained.
A clean-voided specimen is preferred in toilet-trained children.
Urine obtained for culture should be processed as soon as possible after collection.

23. Are not particularly helpful in the diagnosis of UTI and are
not routinely necessary in children with suspected UTI
Other laboratory tests
Markers of
inflammation
Serum
creatinine
Blood culture
Lumbar
puncture

25. DIAGNOSIS OF UTI
UTI is best defined as significant bacteriuria in a patient with pyuria.
If the urine culture demonstrates significant growth
of Enterococcus, Klebsiella, or Pseudomonas aeruginosa in a child
with symptoms of UTI, UTI may be diagnosed in the absence of pyuria

26. Significant bacteriuria
depends upon the method of collection and the identification of the isolated organism.
Clean voided sample:
• significant bacteriuria is growth of ≥100, 000 CFU/mL of a single uropathogen;
• a second uropathogen with growth <50,000 CFU/mL is permitted,
Catheter sample
• significant bacteriuria is growth of ≥50,000 CFU/mL of a single uropathogen
• a second uropathogen with growth <10,000 CFU/mL is permitted,
• children who have growth of 10,000 to 50,000 CFU/mL should have a repeat urine culture.
• It is considered sig. if the 2nd culture grows ≥10,000 CFU/mL and pyuria is present on urinalysis.
●Suprapubic sample
• significant bacteriuria is growth of any uropathogenic bacteria
• (the growth of one colony on the plate is equivalent to 1000 CFU/mL).
Lactobacillus spp, coagulase-negative staphylococci, and Corynebacterium spp are not considered clinically
relevant uropathogens

27. The AAP UTI guideline, published in 2011 and reaffirmed in
2016, recommends both pyuria and 50,000 CFU/mL be present
in febrile infants
The criterion of ≥50000 CFU/mL remains the current standard,
but clinicians may want to consider ≥10,000 CFU/mL in
catheterized specimens from young infants at risk for UTI and
have both fever and pyuria.
In 2012, the Italian Society of Pediatric Nephrology issued
guidelines recommending the threshold be ≥10,000 CFU/mL
for specimens collected by catheterization.

28. False negatives
A bacteriostatic
antimicrobial agent is
present in the urine
Rapid rate of urine
flow with reduced
incubation time
Obstruction of the
ureter
In such cases, Renal scintigraphy may be helpful

29. Pyuria is not specific for UTI.
Pyuria is absent in approx 10 % of children with UTI
• Early in the course of UTI
• Colonization (eg, asymptomatic bacteriuria)
• With certain uropathogens
(Enterococcus species, Klebsiella species, P. aeruginosa)
If the urine culture demonstrates significant growth of Enterococcus, Klebsiella, or
P. aeruginosa in a child with symptoms of UTI, UTI may be diagnosed in the
absence of pyuria.

30. In children who are suspected of having UTI based on a positive
culture, but in whom pyuria is not detected urinalysis, repeating
the urinalysis and urine culture can help to distinguish between
early infection and colonization
Presence of Pyuria
and bacteriuria:
UTI
The absence of
pyuria and
bacteriuria:
bacterial
contamination of the
initial sample
Bacteriuria without
pyuria:
asymptomatic
bacteriuria

31. DIFFERENTIAL DIAGNOSIS
Asymptomatic bacteriuria
• colonization of the urinary tract with bacteria in
the absence of inflammation
• occurs in 1 to 3 % of infants and preschool-age
children, and 1 % of older children.
• in most children, it resolves spontaneously
without causing renal scarring/renal dysfunction
• antibiotic treatment is not recommended.
Other considerations
• DDx depends upon the presenting symptoms
and signs.
• well-appearing infant with fever without focus:
UTI and occult bacteremia.
• urinary symptoms and bacteriuria may be
caused by nonspecific vulvovaginitis, irritant
urethritis, urinary calculi, urethritis secondary to
a STDs, and vaginal foreign body.
• Patients with group A streptococcal infection,
appendicitis, and Kawasaki disease may present
with fever, abdominal pain, and pyuria.
• Bowel and bladder.

32. UTI: ACUTE
MANAGEMENT

33. Elimination of infection and prevention of urosepsis
Relief of acute symptoms
Prevention of recurrence and long-term complications:
• hypertension,
• renal scarring,
• Impaired renal growth and function

34. Management
Acute management
antimicrobial therapy to
treat the acute infection
evaluation for possible
predisposing factors
(eg, urologic
abnormalities).
Long-term
management
prevention of recurrence
and complications

35. Inpatients or outpatient?
Usual indications for hospitalization
• Age <2 months
• Clinical urosepsis
• Immunocompromised patient
• Vomiting or inability to tolerate oral medication
• Lack of adequate outpatient follow-up
• Failure to respond to outpatient therapy
Most infants older than two months with UTI can be safely managed
as outpatients

36. ANTIBIOTIC THERAPY
Antimicrobial
therapy for
children with
presumed
UTI depends
upon a
number of
factors,
including:
• the age of the child, severity of illness,
• presence of vomiting,
• duration of fever,
• underlying medical and/or urologic
problems,
• the antimicrobial resistance patterns in
the community.

37. • Early and aggressive antibiotic therapy (eg, within 72 hours of
presentation) is necessary to prevent renal damage.
• Empiric antimicrobial therapy should be initiated immediately after
appropriate urine collection in children with suspected UTI and a
positive urinalysis. Especially for children who are at increased risk
for renal scarring, including those with:
Fever (especially
>39°C or >48
hours)
Ill appearance
Costovertebral
angle
tenderness
Known immune
deficiency
Known urologic
abnormality

38. A Gram-stained smear of the urine, can help guide
decisions regarding empiric therapy.
The ultimate choice of antimicrobial therapy is based
upon the susceptibilities of the organism isolated.
 Escherichia coli accounts for 80% of UTI in children.
Empiric therapy for UTI in infants and children should
provide adequate coverage for E. coli.

39. • For E. coli:
• Approx 50 % are resistant to amoxicillin or ampicillin.
• Resistance to 1st-generation cephalosporins, Augmentin
or ampicillin-sulbactam, and TMP-SMX have been reported.
• Risk factors for resistance to narrow-spectrum antibiotics include
• lack of circumcision in boys,
• bowel and bladder dysfunction,
• receipt of antibiotics in the previous 6 months
• Hispanic ethnicity

40. • 3rd-generation cephalosporins and aminoglycosides are appropriate
1st-line agents for UTI in children.
• When Enterococcal UTI is suspected
• Those with a urinary catheter, instrumentation of the urinary tract, or
an anatomical abnormality),
• amoxicillin or ampicillin should be added.

41. Oral therapy
Most children > 2 months of age who are not vomiting
can be treated with oral antimicrobials
cephalosporin are the first-line oral agent in the
treatment of UTI in children w/o GU abnormalities.
Oral amoxicillin-clavulanate also was shown to be
effective

42. Oral therapy
First UTI > 1 episode of UTI
1st or 2nd generation
cephalosporins
Amoxicillin clavulanic acid
In a child with Beta lactam
allergy,
• TMP-SMX, or ciprofloxacin is a
reasonable strategy.
Check the previous culture
result
Cefixime
2nd generation
cephalosporins
Trimethoprim
sulfamethoxazole

43.  Fluoroquinolones (eg, ciprofloxacin) are effective for E. coli.
 Use only for UTI caused by Pseudomonas aeruginosa or other MDR gram-
negative bacteria.
 Oral agents that are excreted in the urine but do not achieve
therapeutic serum concentrations (eg, nalidixic acid, nitrofurantoin)
should not be used to treat UTI in febrile infants and young children in
whom renal involvement is likely

44. Cephalosporins and aminoglycosides are appropriate
first-line parenteral agents for empiric treatment of
UTI in children.
Definitive therapy is based upon the results of urine
culture and sensitivities.
Ampicillin should be included if enterococcal UTI is
suspected.
Parenteral antibiotics should be continued until the
patient is clinically improved (eg, afebrile) and able to
tolerate oral liquids and medications

45. parenteral antibiotics
Ampicillin
(100 mg/kg/day in
4 doses)
Gentamicin
(7.5 mg/kg/day IV
in 3 doses)
Ceftriaxone
(50 to
75 mg/kg/day)
Cefotaxime
(150 mg/kg/day in
3-4 doses)
Gentamicin
Beta lactam
allergy

46. Outpatient parenteral therapy
• Once-daily parenteral administration of gentamicin
or ceftriaxone
• Candidates:
• age ≥3 months,
• unable to tolerate oral therapy
• nontoxic appearing
• well hydrated
• without urologic abnormalities,

47. • Patients who have recently been treated with antibiotics are
more likely to have a uropathogen that is resistant to that agent
• pending culture and susceptibility results, they may require an
antibiotic from a different class.
Recent antibiotic exposure
• Review of the antimicrobial susceptibilities of the most recent
urinary pathogens can be helpful in choosing empiric therapy for
children with recurrent UTI.
Recurrent UTI

48. short-course antimicrobial therapy (2-4 days) is effective as
standard duration (7 - 14 days) therapy in eradicating bacteria
in children with suspected lower UTI (afebrile)
short-course therapy may enable clinicians to limit the duration
of exposure to antimicrobials, reducing the likelihood of
adverse events and the emergence of bacterial resistance

49. longer course of therapy is used for febrile children (usually 10 days)
and a
short course of therapy (3-5 days) is used for immune-competent
children presenting without fever.
Oral antibiotics can be used to complete the course of therapy for
patients who are initially treated with parenteral antibiotics.
•When the patient is tolerating oral fluids and has been afebrile for 24 hours.
•There is no minimum duration for parenteral therapy

50. The clinical condition of most patients improves within 24 - 48
hours of initiation of appropriate antimicrobial therapy
The mean time to resolution of fever is 24 hours, but fever may
persist beyond 48 hours
In children whose clinical condition worsens or fails to improve
as expected within 48 hours of initiation of antimicrobial
therapy,
 Broadening antimicrobial therapy may be indicated
 Renal and bladder ultrasonography should be performed ASAP (renal
abscess or surgically correctable anatomic abnormalities or
obstruction)

51. Repeat urine cultures after
48 hours of therapy if
the patient fails to respond clinically
or the uropathogen is not
susceptible to the antibiotic that is
being used for treatment.
• for children who had the
expected clinical response
and the uropathogen is
susceptible to the antibiotic
that is used.
• it is not necessary to repeat
urine cultures during
antimicrobial therapy to
document sterilization of the
urine.

52. Decisions regarding prophylactic antibiotics for children
following initial febrile UTI should be made on a case-by-
case basis.
The 2011 AAP practice guideline does not recommend
prophylactic antimicrobials following the first febrile UTI in
children 2 to 24 months.
The United Kingdom's NICE guideline for UTI in children
indicates that antibiotic prophylaxis should not be
routinely recommended in infants and children following
their first UTI but may be warranted after recurrent UTI.

53. ADJUNCTIVE THERAPIES
Dexamethasone
decreased urinary levels of
interleukin-6 and interleukin-8 in
children,
Possible prevention of scar
formation.
• Additional studies are
necessary to confirm these
results and to determine the
optimum glucocorticoid
regimen before adjunctive
glucocorticoids are routinely
recommended in the
treatment of UTI in children.

54. If such abnormalities are detected, steps can be taken to modify the
risk of subsequent renal damage
surgical intervention antibiotic prophylaxis
to identify abnormalities of the GUT that require additional
evaluation or management (eg, obstructive uropathies, dilating VUR).

55. Ultrasonography:
RBUS can be used to evaluate
• the size and shape of the kidneys,
• the presence of duplication and dilatation of the ureters,
• and the existence of gross anatomic abnormalities.
• renal or perirenal abscess or pyonephrosis
The major advantages of RBUS are
• lack of exposure to radiation,
• Noninvasive
• Helpfulness in predicting risk of renal scarring

56. Children < 2 years of age with
a first febrile UTI
Children of any age with
recurrent febrile UTIs
Children of any age with a
UTI who have a family history
of renal or urologic disease,
poor growth, or hypertension
Children who do not respond
as expected to appropriate
antimicrobial therapy

57. The American Academy of
Pediatrics (AAP)
• recommends RBUS for all
infants and children 2 to
24 months following
their first febrile UTI.
The United Kingdom's
NICE guideline on UTI in
children
• recommends RBUS for
infants < 6 months and
for children > 6 months
who have atypical or
recurrent UTI.

58. Renal US Timing
When RBUS should be performed depends upon the clinical situation.
Aim: to identify complications (eg, renal/
perirenal abscess, pyonephrosis).
ASAP during the acute phase
In infants and young
children with
unusually severe
illness
failure to improve as
expected after
initiation of therapy,
Aim: to reduce the risk of false positive
results
after the acute phase.
For infants and young children who respond as
expected to appropriate antimicrobial therapy,

59. VCUG is the test of choice to establish the
presence and degree of VUR
VUR is an important risk factor for renal
scarring.
 (25 - 30 % of children < 18 years with a 1st UTI
have VUR)
VCUG is expensive, invasive, has radiation
exposure and may miss a significant
portion of children who are at risk for renal

60. VCUG is indicated for:
• Children of any age with ≥ 2 febrile
UTIs
• Children of any age with a 1st
febrile UTI and:
• Any anomalies on RBUS
• The combination of Temp ≥39°C
and a pathogen other than E. coli
• Poor growth or hypertension
watchful waiting (observe, do VCUG
with recurrence)
• For children with a 1st febrile UTI
and without
• abnormalities on RBUS
• Temp ≥39°C + a pathogen other
than E. coli
• poor growth
• Hypertension

61. It remains uncertain whether the benefits of detection and treatment
of VUR after the first UTI outweigh the risks.
The uncertainty centers on the changing view of the role of VUR in
the development of renal damage and progressive kidney disease and
the lack of clarity regarding the effectiveness of medical or surgical
management of VUR in reducing the risk of renal scarring.
Although the risk of renal scarring is increased in children with VUR
compared with children without VUR and increases with increasing
grades of VUR, VUR is neither necessary nor sufficient for the
development of renal scars

62. • recommends postponing VCUG until the 2nd febrile UTI in children 2 - 24
months of age unless there are atypical or complex clinical circumstances or the
RBUS reveals hydronephrosis, scarring, or other findings suggestive of high-
grade VUR or obstructive uropathy
The 2011 AAP clinical practice guideline (reaffirmed in 2016)
• Infants <6 months with atypical or recurrent UTI
• children 6 months – 3 years with atypical or recurrent UTI and dilation on RBUS,
poor urine flow, non-E. coli infection, or family history of VUR.
The United Kingdom's NICE guideline suggests VCUG for

63.  AlthoughVCUG is often scheduled several weeks after
UTI, it may be performed ASA the patient is
asymptomatic.
 Early imaging (as early as the 1st week) does not appear
to falsely increase the detection ofVUR.
 To avoid the use of prophylactic antibiotics in children
w/oVUR, recommendation is to doVCUGs
 during the last days of antimicrobial therapy
 or immediately after completion of antimicrobial
therapy for UTI.

64. Renal scintigraphy

65. RENAL SCINTIGRAPHY
Renal scintigraphy using (DMSA scan) can be used to detect acute
pyelonephritis and renal scarring.
The role of DMSA scan in the management of acute UTI is
controversial.
Scintigraphy at the time of an acute UTI provides information about
the extent of renal parenchymal involvement.
DMSA will identify most (>70 %) children with moderate to severe VUR
(Grade III or higher).

66. some experts suggest that DMSA be used as the initial imaging
test to identify children at higher risk for renal scarring
However, using DMSA as the initial test to identify high-risk
children is more expensive and involves greater exposure to
radiation. Furthermore, it may lead to identification of a large
number of children who may or may not be at risk for future
UTI.
It is unclear how to best manage children with positive acute-
phase DMSA scan.
 Careful clinical follow-up of all children with UTI may obviate
the need for routine DMSA.

67. AAP and NICE guidelines suggest not using DMSA in the
routine evaluation of children with first UTI
Some experts recommend DMSA 6 - 12 months after acute
infection to detect the formation of scarring which would
require follow-up.
The NICE guidelines recommend DMSA 4-6month s after
acute infection for children < 3 years with atypical or
recurrent UTI and for children > 3 years with recurrent UTI.

69. FOLLOW-UP
Recurrent UTI is a risk factor for renal scarring.
Infants and young children with a hx of febrile UTI or with
bowel and bladder dysfunction
 should seek prompt evaluation for subsequent febrile illnesses
 The evaluation of these episodes should include urinalysis and urine
culture.
Among children < 6 years, the risk of recurrence appears to be
increased in those
 who are white, age 3 -5 years, and those with Grade IV - V VUR

70. Prompt diagnosis and effective treatment of recurrent febrile
UTI and treatment of bowel and bladder dysfunction may be
more important than identifying anatomic or functional
genitourinary abnormalities after the first febrile UTI in
preventing renal scarring.
The risk of renal scarring increases with recurrent episodes of
pyelonephritis:
 5 % after the 1st episode to 10 % after the 2nd, 20 % after the
3rd, 40 % after the 4th, and 60% after the 5th
Primary care follow-up for infants and young children who have
had a febrile UTI should include
 regular monitoring of height, weight, and blood pressure

71. Monitor for recurrent symptoms
Identify and treat bowel and bladder dysfunction
Prevention of recurrent UTI in children without VUR
• Antimicrobial prophylaxis
• Unproven interventions
• Surveillance cultures
• Cranberry juice
• Probiotics

72. Dilating
vesicoureteral reflux
(Grades III to V)
obstructive uropathy Renal abnormalities
Impaired kidney
function
Elevated blood
pressure
Bowel and bladder
dysfunction
refractory to primary
care measures
Indications for referral to a pediatric nephrologist or urologist include

75. Urinary tract infection (UTI) in neonates is associated with
bacteremia and congenital anomalies of the kidney and urinary
tract (CAKUT).
Upper tract infections (ie, acute pyelonephritis) may result in
renal parenchymal scarring and chronic kidney disease.
Neonates with UTI should be evaluated for
 associated systemic infection,
 and anatomic or functional abnormalities of the kidneys and
urinary tract.

76. Febrile term infants:
• Among neonates and young infants who present with fever, reported rates of UTI vary from 7 -
15 %.
• UTI typically presents in the second or third week after birth in term infants.
• The incidence of UTI is low (<2 %) in the 1st few days of life even in neonates who are
bacteremic..
Preterm infants
• Data are limited
• risk increases with decreasing gestational age and birth weight.
• the reported prevalence was 8 %
• extremely low birth weight (ELBW) infants had a greater risk of 13 %

77. Term infants
• E. coli is the most common pathogen (80
% of UTI).
• Other gram-negative bacterial causes of
UTI include Klebsiella,
Proteus, Enterobacter, and Citrobacter.
• Gram-positive pathogens
include Staphylococcus coagulase-
negative species, Enterococcus, and S.
aureus.
Preterm infants:
• Coagulase-
negative Staphylococcus and Klebsiella are
more likely causes of UTI in hospitalized
preterm infants,
• E. coli is less commonly seen
• Candida species, (particularly in ELBW
infants).

78. Term infants:
• Most UTIs in neonates represent upper tract infection rather than simple cystitis.
• Hematogenous spread of had been considered to be responsible for UTI because of the
higher frequency of febrile UTI, which was presumed to be due to bacteremia.
• ascending infection?
• Several virulence factors in E. coli account for the propensity of this organism to cause
UTI. (the pili that facilitate bacterial attachment to the uroepithelium and to ascend into
the kidney).
Preterm infants
• Hematogenous infection likely plays a greater role in preterm infants with UTI, as there is
a higher concordance rate of sepsis than in term infants.

79. HOST FACTORS
Male infants :
• account for 75% of neonates and young infants with UTIs
Uncircumcised males
• Incidence is 10-fold greater in uncircumcised vs circumcised males.
• The higher incidence in uncircumcised males is related to an increased rate of bacterial
colonization and enhanced bacterial adherence.
Kidney and urinary tract abnormalities
Prematurity
• because of their relatively immunocompromised status and the use of invasive devices

80.  Term infants
 Abnormalities are seen on US in 35 to 50 % of neonates and
young infants with UTI.
 Most common findings are pelviectasis and mild hydronephrosis.
 Major renal or urologic abnormalities (ie, high
grade hydronephrosis/VUR ) are found in 5 - 10 % of infants.
 Other kidney and urinary tract abnormalities associated with UTI
include:
▪ Urinary obstruction, Ectopic ureter, Renal parenchymal disorders (eg,
PCKD, renal dysplasia)

81.  Preterm infants
 The prevalence of renal or urologic abnormalities would be expected
to be lower
 Among preterm infants with UTI in NICU, abnormalities were seen
on US in 35 -40 %.
 Most common findings were pelviectasis and mild hydronephrosis.
 Major findings were seen in 5 % of patients (high grade
hydronephrosis/VUR, renal dysplasia, unilateral agenesis, partial
duplication of the collecting system, and horseshoe kidney.)

82. Term infants
• signs and symptoms of UTI in neonates are nonspecific.
• The most common clinical findings are:
• Fever
• Poor feeding , FTT
• Jaundice: typically is conjugated
• Vomiting, Loose stools
• UTI may be the presenting manifestation that identifies a neonate with an underlying
congenital anomaly of the kidney and urinary tract (CAKUT)
Preterm infants:
• The clinical manifestations of UTI in preterm infants are similar to those of term infants, with
the addition of apnea and hypoxia.

83. Laboratory tests:
Initial laboratory testing for evaluation
of UTI in neonates includes:
CBC with
differential
Urinalysis Urine culture Blood culture
For febrile or
ill-appearing
neonates, the
evaluation
should also
include LP

84. A urinalysis (microscopic and a dipstick analysis) includes
testing for leukocyte esterase and nitrite.
Urinalysis should always be performed in conjunction with a
urine culture to confirm or exclude the diagnosis of UTI in
neonates.
 The presence of pyuria can be used to support a diagnosis of UTI
when the colony count of a catheterized specimen falls between
10,000 and 50,000 CFU/mL.
Urine should be obtained by either catheterization or
suprapubic aspiration.

85. Urine culture
Diagnosis of UTI is based upon a
positive urine culture collected
by bladder catheterization or
suprapubic aspiration (SPA).
"Clean voided" bag urine samples
should not be used for culture
The number of CFU defining a
positive urine culture varies
based on the method of
collection
• growth of a single pathogen
with a colony count of
≥50,000 CFU/mL,
• or a colony count between
10,000 and
50,000 CFU/mL with
associated pyuria
Bladder catheterization
•growth of a urinary pathogen is significant.
•The growth of one colony is equivalent to
1000 CFU/mL.
Suprapubic aspiration

86. * because the signs and symptoms of neonatal UTI are
nonspecific, several other disorders may present with
similar findings.
* Other infectious conditions including sepsis and
meningitis
 Cultures of urine and other body fluids (eg, blood,
cerebrospinal fluid) distinguish UTI from these other infectious
diseases.
* Inborn errors of metabolism

87. 1. Sepsis evaluation:
• should be obtained in all infants in whom UTI is suspected
• The risk of concurrent sepsis in neonates with UTI varies from 4 to 7 % in
term neonates. The risk is greater in preterm infants
• A positive blood culture does not alter initial management in most patients,
but it may alter the duration of therapy.
A blood culture
• should be performed in ill-appearing infants or those with a fever
• 1-3% of infants with UTI have bacterial meningitis.
Lumber Puncture

88. * Because of the high prevalence of urinary tract abnormalities,
radiographic evaluation should be done for all neonates with
UTI.
* The first step renal US to identify structural abnormalities.
* VCUG is used to evaluate VUR in neonates with
 abnormal renal ultrasound,
 non-E. coli pathogen,
 or recurrent UTI.

89. A renal US should be obtained after treatment is
initiated and the infant's condition has stabilized.
If prenatal US was normal and the study results are
accessible, postnatal renal US may not be necessary.
A normal US does not exclude VUR or renal scarring

90. VCUG should be performed in neonates with abnormal US.
Expert opinion differs whether VCUG is necessary in neonates
with normal US
 "wait and watch" for most neonates with first-time UTI and normal renal US
 VCUGs are generally performed only in neonates with abnormal renal US,
non-E. coli pathogen, or recurrent UTI.
 VCUG is done in all neonates with first-time febrile UTI.
If a "wait and watch" approach is used, patients should be
monitored for recurrence.
 If the patient develops a subsequent UTI, evaluation with VCUG is
appropriate.

91. Renal cortical scintigraphy (DMSA) may be used to
identify renal scarring and acute changes due to
pyelonephritis.
It is not generally helpful in the acute setting but may
be obtained as part of follow-up evaluation
particularly if renal damage is suggested by US.
Although CT also can identify these findings, it is not
suggested for routine use because of the exposure to
radiation.

92. TREATMENT
 Treatment with intravenous broad-spectrum antimicrobial agents should
be initiated as soon as cultures (urine, blood, and CSF) have been
obtained.
 Choice of agent and dosing
 Initially parenteral empiric antibiotic therapy, then organism-specific therapy
based on the isolated organism and its antibiotic susceptibility.
 Empiric therapy
 The choice and dosing of empiric antibiotic therapy is the same as for neonatal
sepsis.
 The combination of parenteral ampicillin and gentamicin provides coverage
for the most common bacterial pathogens.

93. Dosing
Doses are dependent on the weight and
chronologic age of the infant
Weight >2 kg
• ≤7 days
• ampicillin: 50 mg/kg/dose Q 8 hours
gentamicin: 4 mg/kg/dose Q 24 hours.
• >7 days
• ampicillin is 50 mg/kg/dose Q 6 hours;
gentamicin: 4 mg/kg/dose Q 24 hours.
Weight ≤2 kg
• ≤7 days:
• ampicillin: 50 mg/kg/dose Q 12 hours
gentamicin is 5 mg/kg/dose Q 48 hours.
• >7 days
• ampicillin: 50 mg/kg/dose Q 8 hours ,
gentamicin dosing is 5 mg/kg/dose Q 36 hrs

94. The choice of empiric regimen also depends on the clinical setting:
For hospital-
acquired infections,
vancomycin is
substituted
for ampicillin
If meningitis is also suspected,
higher doses of
antibiotics must be
used.
In infants >7 days old, a
third generation is added,
pending culture results

95. Organism-specific therapy
• based upon the isolated pathogen, its antimicrobial susceptibility, and if there
are concurrent infections
Response to therapy
• sterilization of the urine should occur within 48 hours of treatment
• Optimally, it should be confirmed by repeating the urine culture at that time
Duration of therapy
• the duration of antibiotic therapy is 10 - 14 days for neonates with
uncomplicated bacterial UTI.
• Longer treatment is often needed for fungal infections.
• antibiotic prophylaxis with oral amoxicillin (15 -20 mg/kg/day) is started until
radiographic evaluation has been performed.

97. febrile female child suspected to
have UTI
< 2 years
≥ 1 risk factor*
urine analysis
and culture
clinical FU in 24 hours
and reassess the risk of
UTI
dysuria or frequency
urine analysis
and culture
abdominal pain
back pain
or new onsent incontinenece
urine analysis and
culture
UTI
unlikely
Risk factors:
 history of UTI,
 T>39°C,
 fever without
source
 ill appearance,
 suprapubic
tenderness
 fever >24 hours,
 nonblack race
Whom to treat?
• children with Fever
(especially >39°C or >48
hours),
• Ill appearing,
• has costovertebral angle
tenderness,
• with known immune
deficiency,
• with known urologic
abnormality
yes
yes
yes
No No
No

98. febrile male child suspected to have UTI
< 2 years
circumcised
≥ 2 risk factor or
suprapubic
tenderness?
urine
analysis
and culture
clinical FU in 24
hours and
reassess the risk
of UTI
uncircumcised
≥ 1 risk factor
urine
analysis and
culture
clinical FU
in 24 hours
and
reassess
the risk of
UTI
> 2 yesrs
circumcised
consider UA if
multiple
urinary
symptoms
uncircumcised
dysuria or
frequency?
abdominal pain, back pain,
or new onsent
incontinenece
urine
analysis and
culture
UTI
unlikely
urine analysis and
culture
• Whom to treat?
• children with Fever
(especially >39°C or >48
hours),
• Ill appearing,
• has costovertebral angle
tenderness,
• with known immune
deficiency,
• with known urologic
abnormality
yes
yes
yes
yes
yes
No
No
No
No

99. First time UTI: Recurrent UTI > 1 time
 First generation cephalosporin
 Amoxicillin/clavulanic acid
 Second generation cephalosporin
 Check the previous culture result
 Cefixime
 Second generation cephalosporin
 Trimethoprim sulfamethoxazole
In a child with Beta lactam allergy: Trimethoprim sulfamethoxazole

100. • Age <3 months
• Clinical urosepsis (eg, toxic
appearance, hypotension, poor
capillary refill)
• Immunocompromised patient
• Vomiting or inability to tolerate oral
medication
• Lack of adequate outpatient follow-up
• Failure to respond to outpatient
therapy
admission
• Ampicillin + Gentamicin
• Gentamicin
• Ceftriaxone
• Cefotaxime
• For beta lactam allergy:
• Gentamicin or amikacin.
• If ill appearing use two agnets:
aminoglycoside + a
flouroquinolone
Parenteral antibiotics for
inpatients

101. Duration
• Febrile UTI: for 10 days
• lower UTI: for 3-5 days
when to repeat urine culture (after 48 hours of therapy)?
• If the patient fails to respond clinically
• If the uropathogen is not susceptible (intermediate or resistant) to the
antibiotic that is being used for treatment.

102. Imaging:
 Renal US
 After the acute phase.
 Children < 2 years of age with a 1st febrile UTI
 Children of any age with
 recurrent febrile UTIs
 who have a family history of renal or urologic disease,
 Who have poor growth, or hypertension
 ASAP during the acute phase
 with unusually severe illness and who do not respond as expected to
appropriate therapy

103. Imaging:
 VCUG:
 Children of any age with ≥ 2 febrile UTIs
 Children of any age with a 1st febrile UTI and:
 Any anomalies on RBUS, Poor growth or hypertension
 DMSA scan:
 4-6month s after acute infection
 for children < 3 years with atypical or recurrent UTI and for children > 3
years with recurrent UTI

105. VCUG if abnormal US, recurrent UTI, other than Ecoli
Renal US once stabilized
Start empiric antibiotics: ampi/Genta
Complete septic Workup: CBC, blood cx, LP
Take urine cx, UA
Febrile NB  Vancomycin and
gentamicin: For
hospital-acquired
infections
 If meningitis is
suspected,
 Use higher doses
of antibiotics
 In infants >7 days
old, add 3rd
generation
cephalosporin