Presentation on theme: "Overview of Common Obstructive Uropathy in Childhood"— Presentation transcript:
1 Overview of Common Obstructive Uropathy in Childhood DR RM AKUSEConsultant Paediatric Nephrologist,Ahmadu Bello University Teaching Hospital Zaria
2 DEFINITIONObstructive uropathy(OU) is a condition in which the flow of urine is blocked along the urinary tract.The hindrance may be structural or functional.if left untreated can lead to injury to kidney(s) and renal failure.
3 WHY WORRY? Cause of morbidity and mortality in children – CKD, HYPERTENSION, UTIUPTH ( ), 20 CHILDRENHYPERTENSION- 50%RENAL FAILURE- 30%DEATH - 35%Accounted for 16.5% of all pediatric renal transplants in 1997
5 RENAL FAILURE DUE TO OU 30-70% of all End stage renal disease (ESRD) NIGERIAUPTH- 30%UBTH - (9.6%)CALABAR – 6.7%OAUTH- 8%
6 Types Can occur in any part of the urinary system, In children often congenitalAssociated congenital abnormalitesCLASSIFICATIONCongenital/AcquiredAcute/ChronicAnatomical- level of obstructionUnilateral/Bilateral
8 Types BLADDER Neurogenic Stones Tumors or masses around the bladder neck or urethraScarringRetroperitoneal fibrosisURETHRAPosterior and anterior urethral valveAtresiaTumors or massesPhimosisMeatal Stenosis – post circumcision
10 Ardissino et al (2003) OU cause of ESRD in 27.1% of pediatric patients COMMONEST TYPESPosterior urethral valves (23.8%).Ureteropelvic junction (UPJ) obstruction= 3.6%,Obstructive megaureter 3.5%,some form of urethral hypoplasia/atresia 2.3%,ureterocele 1.7%,Other complex uropathies accounted for 5.9%.
11 UPTH – CAUSES OF OU (1997-2002) (n=20) Post urethral Valve -16 (80%),bladder calculi -2 (10%),bladder rhabdomyosarcoma - 1 (5%)urethral stenosis - 1 (5%)
12 PATHOPHYSIOLOGYMECHANICAL DAMAGERELEASE OF BIOCHEMICAL MEDIATORSCELLULAR INFILTRATESFOETAL URINE FLOW IMPAIRMENT
13 MECHANICAL DAMAGE INCREASED INTRATUBULAR PRESSURE LOCAL ISCHEMIA SIGNIFICANT LOSS OF FUNCTIONAL RENAL PARENCHYMASECONDARY REFLUXSUPERIMPOSED UTI.
15 CELLULAR INFILTRATES Macrophages, T-lymphocytes, and fibroblasts glomerular damage,= albuminuriatubular damage= elevated microglobulin alpha-1.tubulointerstitium, - Most damage - Fiborsis
16 FOETAL URINE FLOW IMPAIRMENT Causes deregulation of renal precursor cell turnover and expression of growth factor/survival and transcription factor genes.Renal dysplasia
17 END RESULT HYDRONEPHROSIS, HYDROURETERS, HYPERTROPHIC BLADDER BIOCHEMICAL ABNORMALITIESsometimes type 1 renal tubular acidosis (reduced distal hydrogen secretion)RENAL DYSPLASIA -undifferentiated and metaplastic tissues.OBSTRUCTIVE NEPHROPATHY – bilateral,unilateral
18 Clinical features Consider OU in patients with any of the following: Diminished or absent urine outputUnexplained renal insufficiencyPain that suggests distension in the urinary tractoliguria or anuria alternating with polyuria
19 Clinical features Fever Dysuria Problems with passing urine – incontinence, hesitancy, increased frequencyPoor urinary streamDribblingSymptoms associated with primary disease
20 INVESTIGATIONS URINALYSIS may be normal Abnormal - casts, WBCs, RBCs, albuminuriaUrine MCSUrea, electrolytes, creatinineFBC and differential.IMAGING
21 Abdominal ultrasonography Detection of hydronephrosis.Follow up of hydronephrosisfalse-negative results-if obstruction is early,if obstruction is mildif retroperitoneal fibrosis or tumour encases the collecting systempreventing dilationof the ureter.
22 Voiding cystourethrography (VCUG) Displays anatomy of BLADDER NECK and URETHRAVolume of urine left in the bladder after voidingVesicoureteral reflux,
24 IVU USEFUL when CT cannot identify the level of obstructive uropathy when acute obstructive uropathy is thought to be caused by calculi, sloughed papilla, or a blood clot Must have some renal functionAllergic reactions may occurANTEGRADE OR RETROGRADE PYELOGRAPHY
25 Antegrade pyelogram. stricture of distal ureter in patient with moderate hydroureteronephrosis.
26 CT SCAN/MRICT SCAN- Used when obstruction cannot be shown by ultrasonography or IVU.NOTEultrasonography and CT may not be able to differentiate hydronephrosis from multiple renal or parapelvic cysts.MRI (with or without contrast).used when avoiding ionizing radiation is important (eg, in young children).as accurate as ultrasonography or CT.
27 Radionuclide scans Don’t use contrast agents Can determine perfusion Identifies functional renal parenchymaBUT cannot detect specific areas of obstructionmainly used TOGETHER WITH diuresis renography to evaluate hydronephrosis without apparent obstruction.
28 Diuretic renographyFrusemide given before i.v injection of radiopharmaceutical (Tc 99m DPTA or MAG 3) or IVU).Note- Must have enough renal function to respond to the diuretic.Rate of washout of radionuclide (or contrast agent) is measuredRapid washout - dilated non-obstructed system.Delayed washout - obstructed patternIndeterminate - Washout between 1.5 and 20 minutesFalse-positive and false-negative are common
29 LEFT: complete obstruction of one kidney (upper graph) partial obstruction of other kidney. RIGHT: Discrepancy in function but no evidence of obstruction
30 Foetal urinary electrolytes normal foetal kidney makes hypotonic urinefoetal urinary biochemical markers most useful after 20 weeks' gestationReliability variesfoetal urinary sodium <100 mEq/L andβ-2 microglobulin -more appropriate predictor of postnatal serum creatinine in the foetus
31 INTERPRETATIONA dilated renal collecting system may not mean a true obstruction.HYDRONEPHROSISmust distinguish whether it secondary to an ongoing obstruction or secondary to a prior obstructive event that occurred and resolved antenatally.THIS AFFECTS MANAGEMENT
32 MANAGEMENTA challenge for paediatricians and urologists is to diagnose and intervene appropriately for problemswithout overreacting to variants of normal.
34 COMPLICATIONS CHRONIC KIDNEY DISEASE, ESRF UTI – Chronic or recurrent BLADDER PROBLEMS- incontinence, retentionCALCULI – Renal or uretalComplications due to long-term catheter use
35 PROGNOSIS Duration Specific nature of the blockage, Other factors -Financial constraints- Availability of diagnostic facilitiesequipment drugs
36 Posterior urethral valve (PUV) Commonest cause OU in childrenOccurs sporadically but familial cases have been reportedCause -obstructing membrane in lumen of the posterior (prostatic) urethra.
37 CLINCAL FEATURES broad spectrum of clinical severity The most severe forms do not survive in utero,Mildest forms may go undetected.Antenatallydetected on routine foetal ultrasonography,– hydronephrosis,renal parenchymal echogenicity, renal cysts
38 PRENATAL ULTRASOUND OF FETUS WITH PUV renal dysplasiaSevere hydronephrosis,parenchymal thinning, increased echogenecity of parenchyma.Sagittal view of upper pole of kidney with renal cyst.
39 Ultrasound of bladder of patient with PUV Full bladder with thickened wall and dilated ureters posterior to the bladder (black arrows).Prenatal ultrasound with dilated posterior urethra and dilated bladder (“keyhole” sign).
41 MANAGEMENT - POSTNATALLY ASSESS PATIENTTreat Acute illnessSurgery - Ablation of valveUrinary diversion -vesicostomy, cutaneous ureterostomy,augmentation cystoplasty with later reconstruction.Manage CKDRENAL TRANSPLANTFOLLOW UP - Check for persisting or increasing upper urinary tract dilatation, increasing serum creatinine, bladder problems
42 PRENATAL INTERVENTION Uncertain whether antenatal diagnosis or treatment improves long-term renal outcomeIdentify those who intervention may benefit usinggestational age,amniotic volume,Renal dysplasia - cortical cysts, increased echogenicity.renal function - -urinary electrolytes, β-microglobulin levelsKaryotype
43 Foetal surgery continues to remain controversial. normal outcomes can occur without intervention.Indications? for the carefully selected patient who has normal-appearing kidneys and normal urinary electrolytes with severe oligohydramniosSurgery - vesicoamniotic shunts, valve ablation , bladder marsupialization
44 COMPLICATIONS of interventions Shunt failure and declining appearance of fetal lungs kidney.Chorioamnionitis,Spontaneous ruptures of membrane,amniotic fluid leak.Premature labor with respiratory failure.Fetal mortality rate – 33-43%.
45 POSTNATALLYintervention may not change the prognosis of renal functionWe must not give families unrealistic expectations that fetal surgery is the cure for obstructive uropathy or that the child will not need extensive follow-up after delivery.
46 Outcome BLADDER DYSFUNCTION hyperreflexia, hypertonic, small capacity bladder, sphincter incompetence and/or myogenic failure.End-stage renal disease –Renal failure - in 19% to 64% diagnosed prenatallyin 25% to 40% diagnosed postnatally
47 CONCLUSION:Advances in postnatal surgery and medical management have reduced the mortality in PUVEarlier diagnosis by ultrasound,Developments in surgical techniqueMeticulous attention to neonatal care.
48 UPJ obstruction Intrinsic obstruction hypoplastic adynamic ureteral segment at the UPJExtrinsic causes - aberrant vessels, kinks,PAIN - abdominal or flank -worse with diuresishematuria following mild trauma,chronic nausea, UTI.DIURETIC RENOGRAPHY – may be delayed washoutRx – Nil, surgery, Antibiotics
49 Uretervesical junction (UVJ) OBSTRUCTION hydroureter + HYDRONEPHROSISNORMAL BLADDERmegaureter. - not necessarily obstructed.mainly found incidentally on prenatal sonography,Usually normal physical examUTI, hematuria,abdominal pain or mass,uremia.
50 Management Depends on presence of obstruction presence of reflux, Continued surveillancePatients with nonobstructed system often resolve spontaneouslyantibiotic prophylaxis is recommended until a proper diagnosis can be made.Surgery -
51 SURGERY increasing hydronephrosis on ultrasound, decreasing renal function,Recurrent infectionsPersistent symptomsCalculiCareful follow up
52 The Future? Development of molecular markers for diagnosis and progression? Improve criteria to select patients for treatment? improve prenatal treatment to improve bladder function,? Better imaging techniques???fetal magnetic resonance imaging to assist in differentiating PUV from other causes of severe hydronephrosis, eg, prune belly syndrome,vesicoureteral reflux
53 Prevention need to improve the country's socioeconomic conditions Need to improve health facilitiesmake medical facilities more available to childrenprevent renal diseases that may lead to ESRFEducation at the community level
54 CONCLUSION OU – IMPORTANT CAUSE OF RENAL IMPAIRMENT ADEQUATE MEASURES NEEDED TO PREVENT OR TREAT ESRFRESOURCE CONSTRAINED COUNTRIES – SEVERAL CHALLENGES
56 REFERENCESAnochie I, Eke F.Obstructive uropathy in childhood, as seen in University of Port Harcourt Teaching Hospital, Nigeria. Niger J Med Apr-Jun;13(2):136Michael IO, Gabriel OE. Pattern of renal diseases in children in midwestern zone of Nigeria. Saudi J Kidney Dis Transpl Oct-Dec;14(4):Nasir AA, Ameh EA, Abdur-Rahman LO, Adeniran JO, Abraham MK. Posterior urethral valve. World J Pediatr Aug;7(3): Epub 2011 Aug 7.Etuk IS, Anah MU, Ochighs SO, Eyong M..Pattern of paediatric renal disease in inpatients in Calabar, Nigeria. TropDoct Oct;36(4):256.Eke FU, Eke NN Renal disorders in children: a Nigerian study. PediatrNephrol Jun;8(3):383Woolf AS; Thiruchelvam . Congenital obstructive uropathy: its origin and contribution to end-stage renal disease in children.Adv Ren Replace Ther. 2001; 8(3):157-63 Obstetric uropathy . Considerations for the nephrology nurse. Nephrology Nursing Journal . March 2004Ardissino et al 2003).Nicholas Holmes, Michael R. Harrison, Laurence S. Baskin, Fetal Surgery for Posterior Urethral Valves: Long-Term Postnatal OutcomesObstructive uropathy - OverviewROTH Karl S) ; KOO Harry P. ; SPOTTSWOOD Stephanie E. ; CHAN James C. M.Obstructive uropathy: An important cause of chronic renal failure in childrenCongenital obstructive uropathy: its origin and contribution to end-stage renal disease in children. Adv Ren Replace Ther. 2001; 8(3):157-63 N Eke, SN Elenwo. Obstructiveuropathy in childhood: A review Port Harcourt Medical Journal>Vol 1, No 3 (2007)Casale AJ Early ureteral surgery for posterior urethral valves.. Urol Clin North Am May;17(2):
57 Anochie I, Eke F.Obstructive uropathy in childhood, as seen in University of Port Harcourt Teaching Hospital, Nigeria. Niger J Med Apr-Jun;13(2):136Michael IO, Gabriel OE. Pattern of renal diseases in children in midwestern zone of Nigeria. Saudi J Kidney Dis Transpl Oct-Dec;14(4):Nasir AA, Ameh EA, Abdur-Rahman LO, Adeniran JO, Abraham MK. Posterior urethral valve. World J Pediatr Aug;7(3): Epub 2011 Aug 7.Etuk IS, Anah MU, Ochighs SO, Eyong M..Pattern of paediatric renal disease in inpatients in Calabar, Nigeria. TropDoct Oct;36(4):256.Eke FU, Eke NN Renal disorders in children: a Nigerian study. PediatrNephrol Jun;8(3):383.Woolf AS; Thiruchelvam . Congenital obstructive uropathy: its origin and contribution to end-stage renal disease in children.Adv Ren Replace Ther. 2001; 8(3):157-63 (Obstructive uropathy: considerations for the nephrology nurse. : Nephrology Nursing Journal Publication Date: 01-MAR-04Ardissino et al 2003).Nicholas Holmes, Michael R. Harrison, Laurence S. Baskin,Fetal Surgery for Posterior Urethral Valves: Long-Term Postnatal OutcomesObstructive uropathy - Overview