Urinary tract infection

Urinary tract infection
1-3% of girls and 1% in boys
-peak via infancy and toilet training, after the
1st attack of girls, 60-80% will develop 2nd
attack of UTI, within 18 months
-in boys, more common in 1st year and
much more common in uncircumcised,
-in 1st year M/F 2.4-5.4:1, beyond infancy ,
the ratio is 1:10
Mainly by colonic bacteria, in female, 75-90%
due to E-coli followed by proteus and
Kliebsiella .In male, older than 4 year ,
proteus common as E-coli, reported G+ve in
Staph-saprophyticus is a pathogen in both
Virus(adeno) 11,21 cystitis
UTI have been consider as imported cause
in development of renal insufficiency and end
stage renal disease
Nearly all UTI are secondary from bacteria arise
from fecal flora , colonized the perineum and
enter the bladder via urethra, or from bacteria
beneath the prepuse in
uncircumcised boy , it
may lead to pyelonephritis.
Rarly hematogeneusa
Risk Factors of UTI
uncircumcised boy, vesicouretric
reflux(VUR), toilet training, obstructive uropathy,
urethral insterumentation, wiping from back to
front, bubble bathing, tight clothes, pin worm
infestation, constipation, neuropathic bladder ,
The incidence of UTI in breast fed babies is less
than formula fed.
C/F and Classification
1- Pyelonephritis
is characterized by any or all of the following
Abd pain(flank), fever(may be the only
manifestation), malaise, nausea, vomiting, and
accocianly diarrhea, in newborn and infant,
nonspecific (irritability, jaundice, poor feeding,
weight loss).
 Pyelonephritis is the most common serious
bacterial infection in infants <24 mo of age
who have fever without an obvious focus
 Renal damage, if no called pyelitis
 2- Cystitis
 Baldder involvement, dysurea, frequency,
urgency, malodorous urine, no renal damage,
no fever
 3- Asymptomatic bacterurea
 +ve urine culture but no manifestation, benign
condition , no treatment require except in
Suspected from
symptoms and or finding of urine analysis or
both. +culture for confirmation and appropriate
the DX of UTI, depend on proper sampling of
urine(4 ways)
1- Midstream urine = in child having toilet
training +ve if the colony count more than
100,000 colony –forming units(CFU)of single
MO or child is symptomatic, and 10,000 CFU is
consider UTI, In uncircumcised boy , the
prepuce should be retracted.
2- Adhesive , sealed , sterile collecting urine
bag= in infant, after disinfection of skin of
false-positive rate too high to be suitable for
diagnosing UTI; however, a negative culture is
strong evidence that UTI is absent.
+ve if the colony count more than 100,000 CFU
of single MO and child is symptomatic, and +ve
urine analysis, however if any of this criteria are
not met , we may need next way
proper skin preparation , gentle
technique of catheter is important,
feeding tube polythene nu 5 or nu
8 with lubricant in older child to
decrease risk of trauma, +ve if
more than 10000 CFU of single
4- Suprapubic puncture = +ve
if any MO best method
Prompt plating of urine sample is
important (stay in room temp for
60 min, lead to over growth of
minor contamination the may
suggest UTI), put it in refrigerator.
Others indicators of UTI
A- pyurea (pus cell in urine) suggest UTI,
confirmatory than diagnostic. Conversely, pyuria can
be present without UTI.,so its absence does not
exclude UTI(sterile pyurea)
Sterile pyuria (positive leukocytes, negative culture)
occurs in
1- partially treated bacterial UTIs,
2-viral infections,
3-renal tuberculosis,
4- renal abscess,
5- UTI in the presence of urinary obstruction,
6- urethritis due to a sexually transmitted infection
7-inflammation near the
(appendicitis, Crohn disease),
8- interstitial nephritis (eosinophils)
Continue…Others indicators.
B- Nitrate and leukocytestrase +ve in urine
If a child asymptomatic, GUA normal, it is unlikely
UTI, however, if child symptomatic, and GUA
normal, possible UTI.
C- Blood (neutrophilia, increase ESR, CRP,
in renal abscess, WBC 20,000-25,000, blood
culture is indicated sp in infant(sepsis)
E-Renal Scannig with Techneutiaiumlabeled DMSA(DiMarcoptoSuccinic Acid)
Is the most sensitive and accurate way to detect
the renal scaring.
F- Urogram
less sensitive than DMSA in
detecting the renal scaring, and need 1-2 year to
detect the pathology , risk of radiation
G- CT of abdomin to detect the scaring in
some time.
 should be treated to prevent pyelonephritis
 A- if symptomatic (sever), urine culture should be
obtained, treatment 3-5 days of TrimetheprimSulphmethaxasol(5-10mg/kg), Nitrofurantuin 5-7mg/kg
in 3-4 divided doses(Kliebsiella), Amoxil 50mg/kg is
 B- if symptomatic (less sever ),treatment started till result
of urine culture.
2- Pyelonephritis=
 14 days course of broad spectrum of AB (Ampicillin
(100 mg/kg/24 hr), or Ceftriaxone 50-75mg/kg not
exceed 2 gram)is preferable (less ototoxicity and
nephrrotoxicity), serum cr and level of Gentamycin
should be obtained before and during treatment if
Alkinization of urine is valuble in
cephalosporin(Cefixim) is effective in
G-ve ather than Pseudomonus
effective(contraindicated below age
of 17years, effect the growing
cartlige )
Some outhers suggest loading dose of
Ceftriaxone then oral 3rd generation
In absecce
percuatenus drange
+parental AB
Urine culture should be obtained
treatment(should be sterile)
Indications for hospitalization
A- dehydration
B- unable to drink
C-possiple sepsis
D-age less than 1month
Recurrent UTI
, two or more episodes of UTI with acute
pyelonephritis/upper urinary tract infection, or
pyelonephritis/upper urinary tract infection plus
one or more episode of UTI with cystitis/lower
urinary tract infection, or
• three or more episodes of UTI with cystitis/lower
urinary tract infection.
periodic urine culture every 3months for 2 years (if
child asymptomatic) is indicated.
In recurrent UTI , identify the risk factor and treat
it and give AB prophylactic(1/3 of therapeutic dose)
, Trimetheprime, Nitrofurantuine , Nalidixic acid.,
indicated in
1- neurogenic bladder
2- stasis due to obustruction
Atypical UTI
UTI associated with sepsis or
Concern regarding
obstructive uropathy
Failure to respond to
antibiotics within 48 hours
Associated impaired renal
Infection with a non E. coli
Imaging Study
In children with their
1-1st episode of clinical pyelonephritis
2-Those with a febrile UTI
3- In infants, those with systemic illness
4-A positive urine culture, irrespective of
a sonogram of kidneys and bladder should be
performed to assess
1- kidney size
2-detect hydronephrosis
3- ureteral dilation,
4- identify the duplicated urinary tract
5- and evaluate bladder anatomy.
Next, a DMSA scan is performed to identify whether
the child has acute pyelonephritis. If the DMSA scan
is positive and shows either acute pyelonephritis or
renal scarring,
a voiding cystourethrogram (VCUG) is performed
. If reflux is identified, treatment is based on the
perceived long-term risk of the reflux to the child. One
limitation to this approach is that many hospitals caring
for children with a febrile UTI might not have facilities
for performing a DMSA scan in children. In these cases,
a renal sonogram should be performed, and then the
clinician needs to decide on whether to send the child
to a facility with DMSA capability or instead do a
Time= 2-6 week after infection
1- Radionucltide
less radiation, less
anatomical differentiation
2- Contrast
more radiation , good
Alternative Recommendations for UTI
In 2007
These recommendations divide children into those <6 mo,
6 mo to 3 yr, and >3 yr of age. The clinical categories are
separated into those that
1- respond to treatment within 48 hours
2-recurrent UTI
3- and atypical UTI (sepsis, non–E. coli UTI, suprapubic mass,
elevated serum creatinine, hypertension).
The recommendations include upper tract imaging with a
renal sonogram and DMSA scan for
1- all <6 mo with a UTI
2- All children <3 yr with an atypical or recurrent UTI.
3-For children >3 yr, a DMSA scan is recommended only
for recurrent UTI.
VCUG is recommended only in children <6 mo.
VesicoUretric Reflux(VUR)
IS retrograde flow of urine from the bladder to the ureter and
renal pelvis
Normally , ureter is attached to the bladder in oblique direction
perforating between the bladder mucosa and detroser muscle ,
creating a flap-valve mechanisim that prevent reflux. Reflux occur
when the tunnel between the mucosa and detroser muscle is short
or obliterated.
-reflux usually congenital, run in family (1%), 35%of sibling of a child
with reflux also have a reflux
- reflux in 25% in neuropathic bladder, 50% in boy with posterior
urethral valve, 15%inrenal agenasis
- 20% of ESRD, gave ahistory of reflux
- reflux is important cause of HT in children
pyelonephritis renal scaring
renal insufficaincy ESRD
According to the finding in VSUG
Grade 1 reflux in to nondilated ureter
Grade 2 reflux in to upper collecting system without
Grade 3 reflux in to dilated ureter and or blunting
of calyceal fornices
Grade 4 reflux in to grossely dilated ureter
Grade 5 massive reflux with significant uretral
dilatation and tortuousity and loss of pappilary
Usually discovered during evaluation of UTI, 80% in female , average age is
2-3 year
Renal insufficiency, HT
1- VCUG, reflux occurring during bladder filling is called (low pressure)or
passive and less likely to show spontaneous resolution,
high pressure or active more likely to show spontaneous resolution,
2- Renal U/S
4- Check the Bpr , ht, wt, urine culture
Natural History
1- Grade 1 and 2 ,whether uni or bilateral
spontenous resolution
2- Grade 3 younger age and unilateral
high rate of resolution
3- Grade 4 bilateral less likely to resolve than
4- Grade 5 rarely resolve
The main age of spontaneous resolution is 6
The goal are to 1- prevent pyelonephritis
2- renal insufficiency
3- others reflux complication
Treatment contain the following
1- AB prophylaxis , urine culture
2-VCUG every 12-18 month
3- Check the Bpr , ht, wt frequently
4- the above medical treatment is successful when no infection, and
no scar or reflux resolve
5- Surgical treatment indicated in A- new scar
B- breakthrough UTI
C- not resolve at the age more
than 7 year(failure of medical treatment)
D- Grade 4 and 5