بسم الله الرحمن الرحيم ( وقل ربي زدني علما ). vesicoureteric reflux...

بسم الله الرحمن

الرحيم

) وقل ربي زدني علما (

VESICOURETERIC REFLUX

Dr.Naif AlqarniK.F.H;J

DEFINITIONA retrograde flow of bladder urine into the upper urinary tract.

DEMOGRAPHICS

Prevalence

-10% in general population. -70% in infants with UTI.

-30% in children with UTI -15-25% asymptomatic infants with

Antenatal hydronephrosis.

GENDAR

-VUR usually high grade and bilateral in boys compared with girls.

-Seventy six percent of refluxing infants in male

(Ring et al, 1993.)

-Even though the great majority (85%) of prevailing reflux in older children occurs in females.

DEMOGRAPHICAge

Incidence of Reflux in Patients with Urinary Tract Infections

Age (yr) Incidence )%( < 1 70 4 25

12 15 Adults 5.2

INHERITANCE AND GENETICS

Sibling Reflux

-The prevalence of VUR in siblings to be approximately 32% ( Hollowell and Greenfield, 2002 ).

-Screening ?

-75% are asymptomatic.

INHERITANCE AND GENETICS Sibling Reflux

Reach to 100% in identical twin siblings; (Kaefer et al, 2000 )

The genetic mode of transmission may be autosomal dominant.

INHERITANCE AND GENETICS Genes Involved A prospective screen of the progeny of refluxing patients revealed a 66% rate of reflux in the offspring ( Noe et al, 1992 ) ,

PAX 2 , chromosome 10q: mutations involving renal anomalies (dysplasia, hypoplasia) and VUR.

INHERITANCE AND GENETICS Genes Involved

Glial-derived neurotrophic factor (GDNF) and it’s receptor RET: over expression of RET in mice leads to abnormal placement of the ureteral bud with 30% VUR at birth.

INHERITANCE AND GENETICS Genes Involved

Uroplakin III gene (UPK3) depletion: only in animal and fatal in humans.

Angiotensin receptor 2 (AGTR2): implicated in renal and ureteral developmental anomalies (UPJ obstruction, Megaureter).

FUNCTIONAL ANATOMY OF THE ANTIREFLUX MECHANISMA balance of several factors;

1 -functional integrity of the ureter

UVJ allow intermittent passage of a urinary bolus fashion from the ureter into the bladder and prevent the retrograde flow of bladder urine back toward the upper tracts during storage and micturition.

FUNCTIONAL ANATOMY OF THE ANTIREFLUX MECHANISM

2-anatomic composition of the UVJ

The ureter enters the bladder wall with an oblique intramural path (intramural ureter) and extends through a submucosal tunnel of appropriate length (submucosal ureter) to open onto the trigone in a correct location.


2-anatomic composition of the UVJ

At the extravesical bladder hiatus, the three muscle layers of the ureter separate ,

The outer ureteral muscle merges with the outer detrusor muscle to form Waldeyer's sheath. The latter contributes to formation of the deep trigone.

The middle circular ureteral muscle ends at the level of the hiatus.

The inner longitudinal ureteral fibers form the superficial trigone.


The intramural ureter remains passively compressed by the bladder wall during bladder filling to prevent urine from entering the ureter Flap-valve’ .Adequate intramural length plus fixation of the ureter between its extravesical and intravesical points is required to create this antirefluxing compression valve .

The UVJ in children revealed an approximate 5:1 ratio of tunnel length to ureteral diameter in nonrefluxing junctions versus a 1.4:1 ratio in refluxing UVJs ( Paquin, 1959 ).

Mean Ureteral Tunnel Length and Diameter in Normal Children Age )yr( I.U.L )mm( S.U.L )mm( U.D at UVJ )mm( 1-3 7 3 1.4 3-6 7 3 1.7 6-9 9 4 2.0 9-12 12 6 1.9 From Paquin AJ: Ureterovesical anastomosis: The description and evaluation of a technique. J Urol 1959;82:573.

I.U.L: intravesial ureteral lengthS.U.L:submucosal ureteral length

U.D: ureteral deameter at UVJ


3-functional compliance of the bladder

The existence of local efferent and afferent neuromuscular coordination between the UVJ and the periureteric bladder wall is suggested by neurophysiologic studies that induce an elevation or decrease in intraluminal UVJ pressure during bladder filling ( Shafik, 1996 ).

ETIOLOGY OF VESICOURETERAL REFLUXPrimary Reflux

Represents a congenital defect in the structure and therefore the function of the UVJ.

Reflux occurs despite an adequately low-pressure urine storage profile in the bladder.

The length-diameter ratio of the intramural ureteral tunnel is almost always less than 5:1 ratio .

ETIOLOGY OF VESICOURETERAL REFLUX

Secondary reflux

In normal, mature urinary tract, increasing the intravesical pressure alone does not necessarily induce VUR.


Secondary reflux

Secondary obstruction can be due to anatomical; ureterocele, uretheral stenosis or PUV.

ORfunctional ; neurogenic bladder, non-neurogenic neurogenic bladder, bladder instability.


Secondary refluxAnatomical Causes of Secondary Reflux;PUV :Most common cause,Reflux is present in 48% to 70% of patients with PUVs .

Relief of PUV obstruction appears to be responsible for resolution of reflux in one third of patients only.


Secondary refluxAnatomical Causes of Secondary Reflux;

In females, anatomic bladder obstruction is rare. The most common structural obstruction is from a ureterocele that prolapses into the bladder neck ( Merlini and Lelli Chiesa, 2004 )

ETIOLOGY OF VESICOURETERAL REFLUXSecondary reflux

Functional causes Poorly compliant bladder along with

its abnormal interaction with dyssynergic urinary sphincters can lead to increase interavesical pressures which then weakens and alters the UVJ to cause VUR.McGuire established a strong correlation of bladder pressure more than 40 cmH2O with VUR raised to 80% in patients with neurogenic bladder.

ETIOLOGY OF VESICOURETERAL REFLUXSecondary reflux

Functional causes

Increase in bladder voiding pressures, continence is exchanged for incomplete emptying.Gradual distortion of bladder and UVJ architecture.Structural failure of the UVJ is a critical determinant in creating secondary VUR.


Secondary reflux

Functional Causes of Secondary Reflux;

UTI: ureteral atonylessens compliance, increases intravesical pressures, distorting and weakening the

UVJ ; transient VUR can appear during UTI and resolve after treatment.

International Classification of Vesicoureteral Reflux

Grade Description I Into a nondilated ureter .

II Into the pelvis and calyces without dilatation.

III Mild to moderate dilatation of the ureter, renal pelvis, and calyces with minimal blunting of the fornices .

IV Moderate ureteral tortuosity and dilatation of the pelvis and calyces .

V Gross dilatation of the ureter, pelvis, and calyces; loss of papillary impressions;

and ureteral tortuosity .

DIAGNOSIS AND EVALUATION OF VESICOURETERAL REFLUX

-Antenatal hydronephrosis. -UTI.

-Fever; VUR present in 56% of patients less

than 6months and temp. 38.5.

Renal scarring can occur with a single UTI, even in the absence of a fever.


Radiographic investigation for VUR has generally been directed to ;

-Children with UTI and younger than 5 years ,

-All children with a febrile UTI regardless of age ,

-Any male with a UTI regardless of age or fever.

DIAGNOSIS AND EVALUATION OF VESICOURETERAL REFLUXASSESSMENT OF THE LOWER URINARY TRACT Cystographic ImagingThe basis of reflux detection lies in demonstrating the retrograde passage of an imaging contrast material from the bladder to the ureter and

pelvicalyceal system .

DIAGNOSIS AND EVALUATION OF VESICOURETERAL REFLUXASSESSMENT OF THE LOWER URINARY TRACT Cystographic ImagingVCUG

-provides information on both the functional dynamics and the structural anatomy of the urinary tract.

-Static images record bladder contour, the presence of diverticula or ureteroceles, the grade of reflux, the configuration and blunting of calyces, and intrarenal reflux.

-Passive or active reflux is demonstrated dynamically during fluoroscopy while filling and voiding.

Normal VCUG

Grad V VUR

DIAGNOSIS AND EVALUATION OF VESICOURETERAL REFLUXASSESSMENT OF THE LOWER URINARY TRACT Cystographic ImagingRadionuclide Cystogram :

-Reduces radiation exposure. -More sensitive in some cases.

-Greater role in follow up. -Bladder wall trabeculation, diverticuli, ureteral

duplications and posterior urethral valve cannot be seen.

DIAGNOSIS AND EVALUATION OF VESICOURETERAL REFLUXASSESSMENT OF THE upper URINARY TRACT Renal Sonography

-Nonionizing, noninvasive imaging platform

-Quantitative assessment of renal dimensions,which can then be used to monitor renal growth over time.

u/s Rt. Kidney in pt. with g II reflux In Rt. Duplex system

DIAGNOSIS AND EVALUATION OF VESICOURETERAL REFLUXASSESSMENT OF THE upper URINARY TRACT

Di-mercapto-succinic acid )DMSA( ; -The gold standard for imaging functioning renal

parenchyma. -Document congenital dysplasia.

-Assessment of renal growth and development

-Need 2 studies separated by 8-12 weeks to differentiate pyelonephritis from scar .

Normal DMSA

Left kidney scar

Sever scared Rt. kidney


ASSESSMENT OF THE UPPER URINARY TRACT

Magnetic Resonance Imaging: -Used with gadolinium based contrast

material. -Diagnose reflux, and assess renal

parenchymal scarring. -Catheter to introduce contrast.

-Not sensitive. -Need sedation.

-Child cannot void during study.

CORTICAL DEFECTS Renal scarringCongenital Renal Scarring

Grade of VUR Normal Slight Damage Severe Damage

I-III 13 (100%) IV 8 (53%) 5 (34%)

2 (13%) V 2 (15%) 5 (38%)

6 (46%) Adapted from Marra G, Barbieri G, Dell'Agnola CA, et al: Congenital renal damage associated with primary vesicoureteric reflux. Arch Dis Child Fetal Neonatal Ed 1994;70:F147 .

CORTICAL DEFECTS

Acquired Renal Scarring

Reflux provides a mechanical hydrodynamic mechanism that facilitates the ascension of micro-organisms from the bladder to the kidneys. As such, reflux may be considered an accelerant for renal tissue infection after bacterial colonization of the bladder.

Factors important for acquired renal scarring;

GradeThe frequency of scarring itself appears to be directly proportional to the grade of reflux with which it is

associated ( Winter et al, 1983 ; Weiss et al, 1992b ) .

AgeThe greatest risk for postinfectious renal scarring occurs within the first year of life ( Winberg, 1992 ).The kidney's predilection for postpyelonephritic scarring is inversely proportional to age .

Scarring may still occur beyond 5 years of age ( Smellie et al, 1985 ; Benador et al, 1997 ).

Factors important for acquired renal scarring;

Agescarring in older children is frequently the result of late diagnosis, delayed or inadequate treatment of infection, and social factors that often interfere with patient management. Adults with pyelonephritis and normal urinary tract rarely have scarring.

Complication of renal scarring;

Hypertension, -10-20% of children with reflux nephropathy.

-Related to reflux grade, scarring severity and bilaterality.

-Correction of reflux alone is unlikely to ameliorate blood pressure ( Wallace et al, 1978 ).


Renal failure and End stage renal diseaseThe incidence of chronic pyelonephritis as a primary cause of end-stage renal disease has fallen from 15% to 25% to less than 2% ( North American Pediatric Renal Transplant Committee, 2004).

Reflux remains a leading cause of chronic renal failure in children and young adults in Italy, 25%; mostly > grade III, and 75% are boys.


Reflux NephropathyIt is a radiographic findings:

-Focal parenchymal thinning over clubbed calyx.

-Calyceal dilation with parenchymal thinning.

-Impaired renal growth. -Directly related to grade of reflux.

ASSOCIATED ANOMALIES AND CONDITIONS

Ureteropelvic Junction Obstruction The incidence of VUR associated with UPJ obstruction ranges from 9% to 18%.

Conversely, the incidence of UPJ obstruction in patients with reflux ranges from 0.75% to 3.6%.

High-grade reflux being five times more likely than lower grades of reflux to be associated with UPJ obstruction.


Ureteral Duplication; -VUR is the most common abnormality

associated with complete ureteral duplication.

-Weigert and Meyer Role. -Even in the absence of obstruction from

a ureterocele or ureteral ectopia, duplication with low-grade reflux may take longer to resolve than in single-system reflux


Bladder Diverticula;Cause reflux by 2 ways First, paraureteral diverticulum could compromise the antireflux configuration of the UVJ and cause reflux.Second and more rarely, a large paraureteral diverticulum could expand within Waldeyer's fascia and cause ureteral obstruction.


Bladder Diverticula;Reflux associated with paraureteral diverticula resolves at rates similar to those of primary reflux and should be managed according to the prevailing indications for the reflux itself, irrespective of the diverticulum.


multicystic dysplastic kidney )MCDK(

In the largest series to date, 75 patients with MCDK had a 25% prevalence (19 patients) of contralateral reflux, and half of these were low grade (I to II) ( Miller et al, 2004) .

Spontaneous resolution occurred in a mean of 4.4 years, regardless of grade.Only one patient had reflux corrected surgically .

Pregnancy and Reflux

Bladder tone decreases because of edema and hyperemia, changes that predispose the patient to bacteriuria. In addition, urine volume increases in the upper collecting system as the physiologic dilatation of pregnancy evolves .

MANAGEMENT

Goals of Therapy -Protect upper tract by preventing

pyelonephritis. -Preserve existing renal function in

children with renal impairment.

MANAGEMENT

Principles of Management1 .Spontaneous resolution of reflux is very

common .2 .High-grade reflux is less likely to resolve

spontaneously.3 .Sterile reflux is benign .

4 .Extended use of prophylactic antibiotics is benign .

5 .The success rate with surgical correction is very high.

MANAGEMENT

Spontaneous Resolution Resolution by Grade Most cases of low-grade reflux (grade I and II) will resolve.

63% of grade II ( Duckett, 1983 ) ,80% of grade II ( Arant, 1992 ) ,

85% of grade II (Edwards et al, 1977)

MANAGEMENT

Spontaneous Resolution Resolution by Grade

-Grade III reflux will resolve in approximately 50% of cases ( Duckett, 1983 ; McLorie et al, 1990 ).

-Very few cases of higher-grade reflux (grades IV and V and bilateral grade III) will resolve spontaneously, with not more than 25% ( Weiss et al, 1992 ).

MANAGEMENT

Spontaneous Resolution

Resolution by Age -Resolution rate 20% per year; ( Connolly et

al, 2001) . -The study by Skoog and associates (1987)

observed that reflux resolved in 30% to 35% of subjects each year.

MANAGEMENTSpontaneous Resolution

MANAGEMENT

No scarring at diagnosis;

Grade I-II VUR medical management

grade III-IV VURYounger children medical management.

especially with unilateral older children surgery only if bilateral or

if does not improved.

MANAGEMENT

No scarring at diagnosis;

Grade V VURnewborns and young children medical management initially if able to stay on antibioticsolder children surgery

girls with persistent VUR surgery to prevents complications from future pregnancies

MANAGEMENT

Scarring at diagnosis;Grade I-II medical managementGrade III-IVUnilateral medical managementbilateralyoung children medical managementolder surgeryGrade VNewborns medical manangement

initially >1 year surgery

MANAGEMENT

In newborn patients, it is reasonable to wait until approximately 5 years of age, assuming that no intercurrent breakthrough infections occur.Beyond this age, the kidneys become less prone to scarring after pyelonephritis

(Olbing et al, 2003.)

Medical Managment

-Antibiotic Prophylaxis? -Bladder retraining

-Anticholinergic therapy -α- blocker Therapy

Follow up Assessment

-Urine C/S every 3months. -Yearly radiologic studies.

-Thompson 2005; proposed that a VCUG every other year for lower grades VUR (I, II); and every 3 years in higher grades VUR (III, IV, V).

Follow up Assessment

Upper Tract assesmentU/S and/or DMSAIf there is no symptomatic UTI, it is highly unlikely that new scar will develop.If there is reflux nephropathy, serum creatinine should be assessed regularly.

SURGICAL MANAGEMENTindications for antireflux surgery;

-breakthrough UTIs despite prophylactic antibiotics.

-noncompliance with medical management-severe VUR (grade IV or V) esp. with

pyelonephritic changes.-failure of renal growth, new scars, or

worsening renal function-VUR persisting in girls.

-VUR associated wih congenital abnormalities of the UVJ (bladder diverticulae).

Breakthrough UTI

Pyelonephritis during antibiotic prophylaxis.

Risk OF Breakthrough UTI: -Girls receiving prophylaxis for recurrent

UTI. -Refluxing patient with voiding

dysfunction. -Uncircumcised boys with reflux.

-Children with scarring on DMSA, in both sexes.

Breakthrough UTI

Breakthrough UTI is an indication of failure of non-surgical management.Surgical therapy should be considered.

Surgical Principles of Reflux Correction

•Exclusion of causes of secondary VUR . •Adequate mobilization of the distal

ureter without tension or damage to its delicate blood supply .

•Creation of a submucosal tunnel that is generous in caliber and satisfies the 5:1

ratio of length to width .


•Attention to the entry point of the ureter into the bladder (hiatus), the direction of the submucosal tunnel, and the ureteromucosal anastomosis to prevent stenosis, angulation,

or twisting of the ureter . •Attention to the muscular backing of the

ureter to achieve an effective antireflux mechanism .

•Gentle handling of the bladder to reduce postoperative hematuria and bladder spasms .


Cystoscopycystoscopy in the course of conservative management of VUR is indicated only to confirm or manage abnormalities found on other imaging modalities ( Ferrer et al, 1998 ).

Surgical Principles of Reflux CorrectionCystoscopy

Some surgeons choose to perform cystoscopy at the time of surgery after induction of anesthesia. This is helpful in identifying subtle anomalies not detected on preoperative imaging, particularly if an extravesical technique is used and the bladder is not opened.

Surgical Approaches

Intravesical approach;Politano-Leadbetter Repair.Cohen’s cross-trigonal Repair.Glenn-Anderson Repair.

Intravesical approach;

Advantages and Disantvantage

-High success rate. -Longer hospital stay.

-More pain and bladder spasm. -Higher narcotics and anticholinergic

need. -Typically drained.


Cohen cross-trigonal techniqueuseful in small bladders, thickened bladders gentler ureteral curve.


Cohen cross-trigonal technique

Intravesical approach;Politano-Leadbetter Repair.

Intravesical approach;Glenn-Anderson Repair.

-Less obstruction or kinking, as ureter remains in original hiatus.

-Best candidates are those whose ureters are laterally positioned.


Glenn-Anderson Repair.

Extravesical approach;

Lich-Gregoir

Advantages and Disantvantage

- High success rate 95%.

- Shorter hospital stay.

- Less pain and spasm.

- Lower narcotic and anticholinergic need.

- Typically no drain.

Lich-Gregoir

Surgical Management of VUR

complications of ureteral reimplantationEarly

-VURdue to trigonal edema, usually low grade and transient, treated conservatively.

-Obstructiondue to edema, bleeding, bladder spasms, mucus plugs or clots.Treated with NT or stent if does not resolve.


Complications of ureteral reimplantationLate

-VUR -Failure to achieve sufficient submucosal

length or failure to provide adequate muscular backing: (the most common cause).

-Failure to tailor dilated ureter -Failure to identify and treat secondary causes

of VUR.Treatment: intravesical reimplantation, mucosa of old tunnel incised and scars sharply removed.


Complications of ureteral reimplantationLate

-ObstructionDue to ischemia, angulation at hiatus, inadvertent passage through peritoneum or viscera.

Surgical Management of VURCombined techniquesEndoscopic techniquesLaparoscopic techniques

MEGAURETER

Definition; Ureters wider than 7 to 8 mm can all

be considered MGUs ( Hellstrom et al, 1985 ).

Primary MGU more common in boys

than girls, has a slight predilection (1.6 to 4.5 times) for the left side, and is bilateral in approximately 25% of patients.

In up to 10% to 15% of children the contralateral kidney may be absent or dysplastic.

Classificaton;

Refluxing Obstructed MegaureterA small group of patients have an element of obstruction combined with reflux.Primary refluxing obstructed megaureter occurs in the presence of an incompetent VUJ that allows reflux through an adynamic distal segment.

Six-month-old infant with bilateral massive reflux and obstructive.

Mild obstructed megaureter, showing fullness of the pelvic ureter ,normal proximal ureter, and calyces

Two-month-old boy with bilateral megaureters. A, DTPA renal scan bilateral hydronephrosis and megaureters;left ureter incompletely filled. B, left retrograde pyelogram immediately prior to surgical correction

Note the sharp cut-off at the distal ureter. C, Following transvesical mobilization of the megaureters. The longitudinal channel vessels are preserved and seen through the periureteral adventitia .

D, Postoperative pyelogram following bilateral ureteral plication of the lower half of each megaureter and cross-trigonal ureteroneocystostomy .E, Follow-up radionuclide renal scan.

A, Intravenous pyelogram (IVP) at two months of age, moderate left reflux megaureter .B, IVP at seven months of age, progressive ureteral dilation.

C, IVP at nine months of age, worsening hydroureteronephrosis .D, Voiding cystourethrogram, massive reflux .

E, Postoperative IVP, improved kidney, and ureteral dilatation. Radiologic deterioration despite maintaining sterile urine.

An infant presenting with abdominal distention and uremia .A, IVP shows nonvisualization of the right kidney and severe left hydronephrosis and ureteral tortuosity .

B, Cystogram shows bladder trabeculation, right reflux, and outward displacement of the ureter with filling of a small periureteral saccule .

C, Voiding film, urethral valves, and complete bladder emptying with residual dye filling the bladder saccules and right reflux .

D, IVP following transurethral resection of the valves, bilateral total ureteral tapering, and reimplantation, a satisfactory result.

Evaluation of the megaureter -Presentation:

antenatal hydronephrosis, UTI, abdominal pain,hematuria.

-Urine analysis and C/S. -U/S.

-VCUG. -MAG3 or DTPA.

-Whitaker test.

PRINCEBLE OF MANAGMENT

When renal function is not significantly affected and UTIs do not become a major problem, expectant management is preferredAntibiotic suppression with close radiologic surveillance is appropriate in most cases.


When Hydroureteronephrosis is severe

and shows no signs of improvement In cases in which there is a

documented decrease in renal function In patients with recurrent febrile

infections despite prophylaxis , surgical correction is

undertaken when technically feasible, usually between the ages of 1 and 2 years


For the occasional newborn patients alternative options include

a distal cutaneous loop ureterostomy provides a simple, temporary, low-morbidity solution for poor drainage until the child is old enough to undergo reimplantation.

temporary drainage with an internal ureteral stent.

ManagementRefluxing, non-obstructedprimarymedical management for infants, continued if trend towards improvement seensurgery for older with persistent high-grade reflux endoscopic subureteric injection is recommended .

secondarytreat secondary cause.

Management

Non-obstructed, non-refluxingprimaryMedical management as long as renal function is not affected as UTIs not a problemUS q3-6mosurgical correction by age of 1-2 if no improvement or severe hydronephrosis.secondaryTreat secondary cause.Antenatal MGUObserve: most will resolve.

Surgical correction of MGUs

-Plication or infolding techniques(Starr and Kalicinski).

useful for moderately dilated ureterincreased complications if plicate ureter > 1.75cm in diameter.

-Excisional techniques useful for severely dilated or

thickened ureter.

Technique of ureteral plication and cross-trigonal reimplantation .A, Transvesical mobilization of megaureter .

B, Following ureteral plication .C, Placement of the plicated ureter in a submucosal tunnel .

D, Fixation of the ureter to contralateral wall of bladder .E, Method of ureteric plication (Starr).

Method of ureteric folding(Kalicinski(.

Excisional technique

ComplicationComplications can occur regardless of whether excisional tapering or a folding technique is used

-Stenosis -Reflux

Ureteral obstruction related to postoperative edema

percutaneous nephrostomy and antegrade stenting .)

If persistent, the usual cause is ureteral ischemia ,

revision and excision of the ischemic segment followed

by reimplantation.

THANKS

بسم الله الرحمن الرحيم ( وقل ربي زدني علما ). vesicoureteric reflux...

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