URINARY TRACT INFECTION

1. PRESENTED BY-DR SHUBHENDRA
MODERATOR-DR RAJESH KR. SINGH

2. DEFINITION
• growth of significant number of organisms
• of a single species in urine,
• in presence of symptoms
• Confirmed by positive urine culture
• Recurrent UTI- recurrence of symptoms with significant bacteriuria in patients
who have recovered clinically following treatment.
• Common in girls
ISPN guidelines 2011

3. • Significant bacteriuria- colony count of >105/ml of a single species in
midstream urine sample
• Asymptomatic bacteriuria- significant bacteriuria in absence of
symptoms of UTI
• Simple UTI- UTI with low grade fever, dysuria,frequency and urgency
• Complicated UTI- fever>39⁰C, systemic toxicity,persistent vomiting,
dehydration and renal angle tenderness, raised creatinine
• Recurrent infection- second episode of UTI
Terminologies

4. EPIDEMIOLOGY
• Common bacterial infection in infants and children
• Risk below 14 years- 1-3% in boys
- 3-10% in girls
male female
neonates 5 1
1st year 2.8-5.4 1
Beyond 1-2 years 1 10

5. ETIOLOGY
• 90% of first symptomatic UTI and 70% of recurrent UTI are due to E.coli
Recurrent UTI- proteus and pseudomonas ( also in instrumentation and
nosocomial infections)
Fungi – in immunocompromised
Candida albicans- in preterms
IN GIRLS
E.coli- 75-90%
Klebsiella
proteus
IN BOYS
Proteus = E.coli
Gram positive
IN BOTH
Staph
saprophyticus and
enterococcus

6. Normal Periurethral bacterial flora
• Healthy girls- lactobacilli
• In infants and toddlers- E.coli and enterococci

7. • Neonates: hematogenous spread.
• Beyond neonatal period: ascension of bacteria into the
urinary tract.
• Direct extension of infection occurs in presence of fistula
from vagina or intestine into the urinary tract.
Route of infection

9. I. Female gender
II. Uncircumcised male
III. VUR
IV. Toilet training
V. Voiding dysfunction
VI. Obstructive uropathy
VII. Urethral instrumentation
VIII. Source of external irritation(such a tight
clothing or pinworm infestation)
IX. Constipation
Risk factors for UTI

10. X. Anatomic abnormality(labial adhesion)
XI. Neuropathic bladder
XII. Sexual activity
XIII.Pregnancy
XIV.Broad spectrum antibiotic for minor
infections

11. PATHOGENESIS
• Neonatal period- hematogenous spread
• Other ages- through ascending route and ureters and kidney through
VUR
• Predisposing factors
• Mothers with bacteriuria during pregnancy
• Obstructive uropathy, stones in urinary tract, incomplete emptying,
constipation, threadworm infestation
• 10 times more common in uncircumcised
• Broad spectrum antibiotic therapy for minor infections

12. • Host defence mechanisms
• Some bacteria- expelled with micturition
• Antireflux mechanism of simple and compound papillae
• Intrinsic defence- bladder epithelial cells
- secretory IgA in urine
- blood group antigens in secretions
• Breast feeding- protects in 1st 6 months of life

13. • Bacterial virulence
• Bacterial adhesion- by fimbriae( pili)
Activation of cytokines
Bacterial adhesion
Production of adhesins
Chemotaxis of leukocytes

14. FIMBRIAE
Type 1
On E.coli
Mannose sensitive
Type 2
Mannose resistant
Receptor- Gal1-4 Gal
oligosaccharide
P- fimbriae
No role in
pyelonephritis
Cause
pyelonephritis
76-94%

16. • Virulence factors
• O antigen- inducing inflammation and fever
• Capsular K antigen- resistance to phagocytosis and bactericidal effect
of serum
• Hemolysin- damages uroepithelium
• Aerobactin- scavenging iron from urine

17. • BIOFILM- formation of glycocalyx polymers
- on uroepithelial surfaces, indwelling catheters and diaper
fibers

18. CLASSIFICATION
CLINICAL
PYELONEPHRITIS
CYSTITIS
ASYMPTOMATIC
BACTERIURIA
UTI

19. • CLINICAL FEATURES
PYELONEPHRITIS
• Abdominal back or flank pain, fever, malaise , nausea, vomiting
• Newborns- poor feeding, irritability, jaundice weight loss
• Most common in <24 months
• Renal injury- pyelonephritic scarring
• Acute lobar nephronia- renal mass
• Renal abscess
• Perinephritic abscess- contiguous infection

20. • Xanthogranulomatous pyelonephritis- granulomatous inflammation
with giant cells and foamy histiocytes
Renal calculi, obstruction and proteus infection
total and partial nephrectomy

22. • CYSTITIS
• Dysuria, urgency, frequency, suprapubic pain, incontinence and
malodorous urine
• Acute hemorrhagic cystitis- by E.coli
adenovirus 11 and 21
• Eosinophilic cystitis- hematuria, ureteral dilatation and ocassional
hydronephrosis, filling defects
• Bladder biopsy
• Treatment- antihistamines and NSAIDS, intravesical dimethyl sulfoxide

23. • Interstitial cystitis
• Voiding symptoms and pelvic pain relieved by voiding
• negative urine culture
• Adolescent girls
• Cystoscopic observation of mucosal ulcers
• Treatment- bladder hydrodistension and laser ablation

25. Asymptomatic bacteriuria
• Presence of significant bacteriuria in absence of symptoms of UTI
• 1-2 % in girls and 0.2 % in boys
• Benign condition- no renal injury, no treatment
• Most common- E.coli
• Presence of asymptomatic bacteriuria in previously treated UTI- not
recurrent UTI

26. DIAGNOSIS
• Based on culture of a properly collected sample
• Significant pyuria- >10 leukocytes per mm3( uncentrifuged sample)
- > 5 leukocytes per mm3 ( centrifuged sample)
• Leukocyturia in absent bacteriuria- not sufficient
• Rapid dipstick assays- leukocyte esterase and nitrite
• If child is asympomatic and N urinalysis- UTI unlikely
• If child is symptomatic and N urinalysis– UTI is possible

27. • COLLECTION OF SAMPLE
• A clean catch midstream sample-
• Neonates and infants- suprapubic aspiration or transurethral bladder
catheterization
• Urine sample – plated within 1 hour
• Stored in refrigerator 4⁰C for 12-24 hours
• Urine culture repeated-contamination suspected- mixed growth or
growth of periurethral flora

29. URINE SAMPLE - STORAGE
• If urine is to cultured but cannot be processed
within 30mins of collection , sample is to be
refrigerated at 4 0c upto 12-24hrs.
•
• IAP Standard treatment guidelines 2022

30. Urine microscopy
 Urinalysis: Leucocytes> 5 WBC/HPF in centrifused urine and
bacteriuria.
 Leucocytes > 10 wbc/mm3 in uncentrifused urine and
bacteriutia
Is suggestive of UTI.
 The detection of leukocyturia in absence of significant bacteriuria is not sufficient to diagnose a
UTI.

31. Dipstick test
• Screening tool
• Positive dipstick tests for nitrite reduction and leukocyte
esterase correlate well with urine culture.
(specific)
• Not detected in children with urinary frequency and
enterocoocus.

32. Urine culture
• Diagnostic of UTI
• Gold standard
IAP treatment guidelines 2022

33. • Acute renal infection- lekocytosis,neutrophilia and elevated ESR, CRP
• Renal abscess-WBC- >20,000- 25,000/mm3
• Sepsis common in infants and obstructive uropathy- blood cultures
sent

34. Diagnosis of UTI in young children is made in presence of:
 Symptoms : fever, dysuria, urgency, frequency,
abdominal/flank pain in older children and fever, vomiting,
diarrhea and poor weight gain in infants PLUS ;
 Positive dipstick for leukocyte esterase and nitrite (as a
screening tool)
 Abnormal urinalysis with significant pyuria and bacteriuria
AND
 Isolation of single species of microorganism in significant
number in a properly collected urine sample prior to
starting antimicrobial therapy and tested for urine culture
(gold standard)
IAP satndard treatment
guidelines 2022

35. INITIAL EVALUATION
• Degree of toxicity, dehydration, ability to retain oral intake
• History of bowel bladder habits elicited
• Distended bladder
• Palpable enlarged kidneys
• Tight phimosis, vulval synechiae
• Palpable fecal mass in colon
• Patulous anus, neurological deficits in
lower limbs
• Urinary incontinence
• Previous surgery of urinary tract, anorectal
malformations, meningomyelocele
UNDERLYING STRUCTURAL ABNORMALITY
• Recurrent UTI
• Persistent high grade VUR
• Constipation
• Holding maneuvers
• Voiding <3times/ >8 times a day
• Straining/ poor urinary stream
• Thickened bladder wall>2mm
• Post void residue >20 ml
• Spinning top configuration of
bladder on MCU
BOWEL BLADDER DYSFUNCTION

36. TREATMENT
• <3months and complicated UTI- hospitalized, IV antibiotics
• 3rd generation cephalosporins- preferred
• Single daily dose of aminoglycoside- In normal renal function
• I.V – for 2-3 days- followed by oral
• >3months and simple UTI- oral antibiotics
• Failure to respond- resistance, non compliance

37. • DURATION
• 10-14 days- infants and children with complicated UTI
• 7-10 days- uncomplicated UTI
• adolescents with cystitis- shorter duration – 3days
• Prophylactic antibiotic therapy- below 1 yr( until imaging )

38. antimicrobials
ceftriaxone 75-100 divided B.D
cefotaxime 100-150 B.D or TID
amikacin 10-15, single dose IV or IM
gentamycin 5-6 single dose IV or IM
coamoxiclav 30-35 of amoxicillin, in 2
divided doses IV
parenteral
cefixime 8-10 BD
coamoxiclav 30-35 of amox, BD
ciprofloxacin 10-20 BD
ofloxacin 15-20 BD
cephalexin 50-70 , BD or TID
oral

39. • Acute cystitis
• 3-5 day course of TMP-SMX- effective against E.coli
• Nitrofurantoin(5-7mg/kg/d)- klebsiella, enterobacter
• Amoxicillin(50mg/kg/d)
• Pyelonephritis
• Ceftriaxone(50-75mg/kg/d)
• Cefotaxime(100mg/kg/d) 10-14days
• Ampicillin(100mg/kg/d)
• Gentamicin(3-5mg/kg/d)
Nelson

40. • Oral 3rd generation cephalosporins- cefixime
• In some children – i.m loading dose of ceftriaxone f/b oral cefixime is
effective
• In recurrent UTI-
• Prophylaxis- TMP-SMX or Nitrofurontoin- at 30% of dose
• Amoxicillin, cephalexin

41. • SUPPORTIVE THERAPY
• Maintain adequate hydration
• Routine alkalinisation- not necessary
• Paracetamol for fever
• Repeat urine culture not necessary unless persistence of fever and
toxicity despite 72 hrs of antibiotics

42. Cranberry juice
Prevents bacterial
adhesion
Prevents biofilm
formation

44. EVALUATION OF 1ST UTI
• USG, DMSA scan and MCU
• USG- kidney size, hydronephrosis bladder anomalies and post void
residual urine
• DMSA scintigraphy-renal parenchymal infection and cortical scarring
• MCU- VUR and anatomic details of bladder and urethra

45. • USG – soon after diagnosis
• MCU- 2-3 weeks later
• DMSA- 3 months after treatment
• Hydronephrosis without ureteric dilatation- diuretic renography using
DTPA or MAG-3

47. PREVENTION OF RECURRENT UTI
• GENERAL
• Adequate fluid intake, frequent voiding
, avoid constipation
• Regular and volitional low pressure voiding
with complete bladder emptying
• Double voiding
• circumcision

48. ANTIBIOTIC PROPHYLAXIS
• Long term low dose antibacterial prophylaxis
medication Dose, mg/kg/day remarks
cotrimoxazole 1-2 Avoid in infants <3mo, G6PD def
nitrofurantoin 1-2 Vomiting and nausea,avoid in <3mo, G6PD def,
renal insufficiency
cephalexin 10 DOC in 1st 3-6 mo of life
cefadroxil 5 An alternative agent in early infancy

49. • Indications and duration of prophylaxis
• On patient age and presence or absence of VUR
i. UTI below 1 yr of age while awaiting imaging
ii. VUR
iii. Frequent febrile UTI( >3 episodes in year)
• Not adviced in patients with urinary tract obstruction, urolithiasis and
neurogenic bladder, on CIC

50. • BREAK THROUGH UTI ON PROPHYLACTIC ANTIBIOTICS
• Poor compliance or voiding dysfunction
• Appropriate antibiotics
• Change of medication- not necessary
• No need of cyclic therapy

51. LONG TERM FOLLOW UP
• Renal scar( reflux nephropathy)- need for early diagnosis and therapy,
regular follow up
• Physical growth and BP- monitored 6-12 months
• Urinalysis for proteinuria and blood levels of creatinine
• Annual ultrasound- renal growth

52. • INDICATIONS FOR REFERRAL TO A PEDIATRIC NEPHROLOGIST
• Recurrent UTI
• UTI with bowel bladder dysfunction
• VUR
• Urologic or renal abnormalities
• Renal scar, deranged renal functions, hypertension

53. TAKE HOME MESSAGE
• UTI should be suspected in all cases of fever without focus
• Most cases of UTI are simple, uncomplicated, and respond readily to
outpatient antibiotic treatments without further sequelae.
• Appropriate treatment, imaging, and follow-up prevent long-term
sequelae in patients with more severe infections or chronic infections.
• Any child with proven UTI should have imaging studies performed to
R/O VUR or renal anomalies.

54. References
• IAP Standard treament guidelines 2022
• PEDIATRIC NEPHROLOGY- RN Srivastava, Arvind Bagga(6th edition)
• ISPN guidelines for management of UTI- 2011
• Nelsons textbook of pediatrics- 21th edition
• OP Ghai textbook of pediatrics