1. Urinary Tract Infection in Children Co. Stephanie January 23. 2014

2. Prevalence Occurs in 1-3% of girls, 1% of boys – Girls: usually occurs by 5 yrs of age peaks during infancy and toilet training – Boys: common during the 1 st year of life more common in uncircumcised boys Male:Female ratio 1 st year of life2.8 : 5.4 >1-2 years1 : 10

3. Etiology Main agent: colonic bacteria – 75-90%: caused by E. coli, followed by Klebsiella spp and Proteus spp Proteus spp: common for boys >1 yr of age – Other pathogens: Staph saprophytius and enteroccocus, – Viral causes: adenovirus and other viral infections

4. Risk Factors FemaleWiping from back to front (girls) Anatomic abnormality (labial adhesion) Uncircumcised maleBubble bathNeuropathic bladder Toilet TrainingTight clothing/underwear Sexual activity Voiding dysfunctionPinworm infestationPregnancy Obstructive uropathyConstipationVesicoureteral reflux* Urethral instrumentation Bacteria with P. fimbriae *increase risk for PYELONEPHRITIS

5. CLASSIFICATIONS ①Pyelonephritis Most common serious bacterial infection in infants <24 mo of age who have fever WITHOUT an obvious focus ②Cystitis ③Asymptomatic Bacteriuria

6. PYELONEPHRITIS a.Abdominal, back, or flank pain b.Fever c.Malaise d.Nausea and vomiting e.Occasional diarrhea Indicative of a bacterial infection of the UPPER URINARY TRACT ACUTE PYELONEPHRITIS: WITH renal parenchymal involvement can result to pyelonephritic scarring PYELITIS: NO parenchymal involvement ACUTE LOBAR NEPHRITIS: renal mass caused by acute focal infection without liquefaction; can be an early stage of renal abscess development XANTHOGRANULOMATOUS PYELONEPHRITIS: Rare infection characterized by granulomatous inflammation with giant cells & foamy histiocytes

7. CYSTITIS a.Dysuria b.Frequency c.Urgency d.Suprapubic pain e.Incontinence f.Malodorous urine NO: ✘ Fever ✘ Renal Injury Acute Hemorrhagic Cystitis: often caused by E. coli and Adenovirus types 11 and 21 Adenovirus cystitis: more common in boys; self-limiting infection Eosinophillic cystitis: rare form occasionally found in children Usual symptoms: Hematuria, ureteral dilation with occasional hydronephrosis, and filling defects in the bladder May have been exposed to an allergen Interstitial cystitis: IRRITATIVE voiding symptoms such as urgency, frequency, and dysuria, and bladder/pelvic pain Relieved by voiding with a negative urine culture Most likely affects adolescent girls; idiopathic Indicative of BLADDER INVOLVEMENT

8. ASYMPTOMATIC BACTERIURIA Positive urine culture WITHOUT any manifestations of infection Most common in girls – <1% in pre-school and school-age – Rare in boys Benign condition: does not cause renal injury EXCEPT in pregnant women

9. Pathogenesis: Ascending infection Bacteria arise from fecal flora Colonize the perineum Pass the urethra Enter the bladder CYSTITIS

10. Pathogenesis: Ascending infection CYSTITIS Infection ascends to the kidney ACUTE PYELONEPHRITIS

11. Pathogenesis: ACUTE PYELONEPHRITIS NORMAL kidney: Simple and compound papillae have an antireflux mechanism that prevents urine in the renal pelvis from entering the collecting tubules – Some compound papillae (esp. upper and lower poles) allow for INTRARENAL reflux Infected urine: stimulate inflammatory & immunologic response

12. Diagnosis A urine culture is necessary for confirmation and appropriate therapy (Nelsons 19 th ed) Urine sampling: – Toilet-trained: midstream catch – Uncircumcised boys: retract prepuce first – Not toilet trained: catheterized urine sample A positive culture can result from skin contamination

13. Pyuria Definition: positive leukocytes Infection CAN occur in the absence of pyuria Suggestive of infection; More confirmatory than diagnostic Pyuria can be present without UTI

14. Sterile pyuria Definition: positive leukocytes, negative culture Nitrites and leukocyte are usually positive in infected urine Microscopic hematuria is common but alone does not suggest UTI Partially treated bacterial UTI’sUrethritis due to STI Viral infectionsInflammation near the ureter/bladder (appendicitis, Crohn’s disease) Renal tuberculosisInterstitial nephritis (eosinophils) Renal abscessUTI due to urinary obstruction Asymptomatic child + normal urinalysis = Unlikely that there is UTI Symptomatic child + negative urinalysis result = UTI is still possible Asymptomatic child + normal urinalysis = Unlikely that there is UTI Symptomatic child + negative urinalysis result = UTI is still possible

15. Urine culture POSITIVE RESULT: >100,000 colonies of a single pathogen 10,000 colonies AND Symptomatic child Presumed UTI: Bag sample Positive urinalysis + Symptomatic patient + >100,000 colonies of a single organism Confirm with a catheterized sample if any of the criteria is not met

16. Other tests CBC: leukocytosis, neutrophilia Serum Erythrocyte sedimentation rate: elevated C-reactive protein: elevated

17. Imaging Goals: Determine anatomic abnormalities that predispose to infection Determine whether there is active renal involvement Assess renal function risk

18. Imaging: DMSA renal scan Dimercaptosuccinic acid (DMSA) renal scan Involved areas are photopenic showing enlarged kidneys – Approx. 50% with febrile UTI will have a positive DMSA scan – 50% of those with positive DMSA scans will develop renal scarring

19. Imaging: Voiding cystourethrogram Done for those with evidence of acute pyelonephritis or renal scarring on DMSA scan Can help identify reflux Can be delayed 2-6 wks to allow for bladder inflammation to resolve

20. Treatment Acute cystitis: should be properly treated to avoid progression to pyelonephritis Severe symptoms: presumptive treatment is started pending results of urine culture Mild symptoms/Doubtful diagnosis: delay treatment until culture results

21. Treatment regimen: Acute Cystitis If treatment is initiated before culture results: a.Trimethoprim-sulfamethoxazole (TMP-SMX) or trimethoprim (for 3-5 days): effective against most strains of E. coli b.Nitrofurantoin (5-7mg/kg/24 hr in 3-4 divided doses): effective against Klebsiella and Enterobacter c.Amoxicillin (50mg/kg/24hr): effective but no clear advantage

22. Treatment regimen: Acute Pyelonephritis 10-14 day course of broad-spectrum antibiotics capable of reaching significant tissue levels is preferred Dehydration, vomiting, poor oral intake: signs to admit a child for IV rehydration and IV antibiotic therapy Ceftriaxone (50/75 mg/kg/24hr – not exceed 2g) or Cefotaxime (100mg/kg/24hr) or Ampicillin (100mg/kg/24hr) with an Aminoglycoside (ex Gentamicin 3-5mg/kg/24hr in 1-3 divided doses)

23. Treatment Ciprofloxacin is an alternative agent for resistant microorganisms in patients >17 yr or short course treatment for young children Clinical use of fluoroquinolones in children should be restricted because of potential cartilage damage

24. Treatment: Recurrent UTI a.Identify predisposing factors b.Prophylaxis against reinfection: controversial TMP-SMX, Trimethoprim, Nitrofuratoin at 30% of the normal dose c.Probiotic therapy: replaces pathologic urogenital flora* d.Cranberry juice: prevents bacterial adhesion and biofilm formation*

25. Complications Renal scarring: Highest risk in children <2 years old Renal insufficiency or end- stage renal disease in children Arterial hypertension

26. Thank you.