UTI is a frequently occurring bacterial infection with an incidence of 7% in girls and 2% in boys in first 6 yrs of life.UTI can cause development and progression of renal parenchymal damage (renal scars) resulting in hypertension, chronic renal insuff.and toxemia of pregnancy on long term follow up.After initial evaluation and treatment of the first attack of UTI according to age a plan for long term management should be chalked for “high risk” children.
Initial management of UTI
Suspect = All febrile children
Diagnose = Urine culture, colony count ASAP
Treat = Promptly within 72 hrs of fever

with appropriate drug for 10-1:: days, Investigate for underlying lesions Identify “High risk group” requiring long term management.

Marks (2008) Unresolved, complicated, recurrent UTI

Abnormal prenatal US, clinical clues – “Highrisk” :
“High Risk”(15-20%) “Low Risk” (80%)
::USG abndilation of kidney and/urinary tract – No
(PUV,VUR,PUJ ETC.)

::Neonatal sepsis Febrile but no bacteremia
::Poor urinary stream renal lumps clinically – N
::Non E.coli infn. E.Coli infection
::Poor/incomplete Response to drug Rx complete resolution with
appropriate drug Rx
::Complicated UTI Recurrent UTI No
::Immune def. No
::Voiding dysfunction No (toilet trained)

Aims of long term management of UTI
::To prevent recurrent UTI → scars
::To prevent new renal scars → renal damage and monitor old scars.
::To detect abn. that req. surgical treatment – PUV, ureterocles, severe PUJ obstr; gr.V VUR, calculi by appropriate imaging protocols.
::To follow this select group of children thro' adolescent to adulthood and treat medical problems like hypertension, persistent proteinuria, chronic renal insuffiency when reqd. with the help of Pediatric nephrologist.

Prevention of recurrent UTI
·::Treatment of predisposing causes
Constipation Rx -diet rich in fibre, ↑ fluid intake Laxatives, PEG Perineal, periurethral hygiene.
::Bladder dysfunction – urinary symptoms, day time wetting, squatting
Rx – :: Timed periodic voiding :: Urinary prophylaxis :: Oxybutynin for irritable bladder with ↓ bladder volume. :: clean intermittent catheter (CIC) when req.
::Low dose antibiotic prophylaxis.
Medical management of recurrent UTI with VUR ± renal scarring
::From 1975 low single night dose of drugs mainly nitrofurantoin/cotriamoxazole (Trimethoprim + Sulfamoxazole) was used to suppress multiplication of bacteria in urinary bladder to prevent rec.UTI./renal scars.
::The efficacy of this Rx in compliant patients was comparable to surgical repair of VUR (gr II-IV) in prevention of new scars and progression of old scars, renal growth, renal function and recurrence of UTI on 10 yr follow up (International reflux study)
:: Jodal 2006, Ped.Nephrol.21:785-792)
:: Wheeler 2003, Arch. Dis. Child 88:688-69::.

Long term low dose urinary prophylaxis
::Cornerstone of medical Rx of VUR/Rec UTI.
:: Night Dose of NFT/ 1mg/kg
Trimethoprim 1mg/kg
Nalidixic acid 20 mg/kg
:: Indications gr II – IV VUR till VUR ↓ or resolves or 7 years age
Post surgery for 3-6 months
Bladder dysfn/neurogenic bladder
Febrile UTI pending investigations.

Problems with long term drug prophylaxis Surveillance:

::For detection of “break through” infections by urine cultures in Febrile children(18-26% per year) Protocol based urine cultures not advised.
::Poor compliance – long treatment.
::Break through infection – Rx ensure compliance or change antibiotic or double prophylaxis.
::Resistant infections.
::Recently probiotics – Lactobacillus, 1 gm = 10 8 CFU twice a day tried.

Surgery for VUR on drug prophylaxis
::Persistent gr IV – V reflux
::Poor compliance, parental preference intolerance to medical treatment
::Circumcision may help to prevent recurrent UTI Surgery does not benefit if renal function ↓ and persistent proteinuria occurs (nephropathy).

Follow up imaging protocols during long term management
::VUR – spontaneous resolution of gr II – III VUR Unilateral or bilateral – in 75 -80%
:: Radionucleid cystography/MCU every 2 years
:: DMSA renal scan for renal scars/2-3 years
:: DTPA renal scan to monitor differential renal function if indicated
:: Ultrasonography /2-3 years to monitor growth of kidneys
VUR gr IV – V Bilateral persistent best treated surgicallyUnilateral slow resolution 5% per year.
::RNC/MCU every 3 years
Neonatal VUR - usually scars are present at birth – resolution in 67-78% in 2 yrs. Secondary VUR: PUV, duplex, ureterocele, neurogenic bladder-resolution variable and depends on bladder dysfunction.

Monitoring of renal parameters
Yearly BUN, S.creatinine, GFR in “high risk group” Proteinuria / microalbuminuria indicates nephropathy Rx ACEI/ARB may be tried to protect kidneys.
::BP monitoring once a year – must and if BP > 99 centile – treatment.
::Other parameters – blood gas, s.electrolytes, S. ca/P/alk PO:: , CBC etc. if S.cr/GFR shows declining renal function. Treatment of stage III CKD by nephrologists

Recent long term (more than 20 yrs follow up) studies have concluded
::Low risk of hypertension, following UTI and renal scarring (7-17%).
::Little evidence that renal scarring secondary to UTI leads to CRF, dialysis or transplantation or pregnancy complications. Arch Ped. Adolesc.Med 2000

CONCLUSION

::Although childhood UTI is common on long term followup Chronic kidney disease is rare.
::Follow up of children with UTI should include urine culture only if fever without focus of infection.
::Yearly wt, ht, BP, routine urinalysis S.creatinine (GFR preferred) to detect growth failure, hypertension proteinuria, or renal insufficiency.
::Imaging studies are important to evaluate gr of VUR and its resolution by periodic MCU
::Renal scars are known to occur till 7 yrs of age and periodic DMSA renal scans are advised to monitor scars.
:: Recent studies do not support earlier reports of efficacy of long term low dose drug prophylaxis in prevention of recurrent UTI, renal scars and ESRD. However resolution of VUR is better and quicker if urine is kept sterile.
:: Treatment of constipation, bladder dysfunction and perineal hygiene important. Early detection and treatment of hypertension and persistent proteinuria can reduce progressive renal damage.

Key Messages

::Long term sequele of childhood UTI are uncommon
::Long term low dose drug prophylaxis is equal to surgery in prevention of recurrent UTI, may reduce the risk of renal scars in children with VUR. Recent data on role of medical/surgical Rx is questionable.
::Yearly growth, B.P. urinalysis and S.Cr./GFR estimation recommended in high risk sub group of children.
::Prompt recognition and treatment of UTI is most effective in preventing renal damage.