الفهرس 
• Epidemiology and DemographicsOnly 14 pages are availabe for public view
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Abstract
Primary vesicoureteral reflux (VUR) has long been recognized as a major child and public health problem, affecting about 1% to 2% of the children (Hayn et al, 2008). Girls are three times boys in affection but boys have more severe pattern. VUR is present in 29%–50% of children with urinary tract infection (UTI) (Silva et al, 2006) and in approximately 10% of infants with antenatal hydronephrosis (Ansari et al, 2009). Also VUR is present in about 14% of cases of UPJ obstruction undergoing pyeloplasty (Hollowell et al, 1989).
The vesicoureteric junction represents an important area between the low pressure of the upper urinary tract and the variable pressure of the lower urinary tract and the region that is most important for preventing VUR. In fact, the anatomy of a normal vesicoureteric junction provides a valvular mechanism which prevents reflux. The submucosal tunnel length through which the ureter runs is an important anatomical factor for this valvular mechanism. Other affecting factors include active muscle control in the UVJ and the intravesical pressure. It was shown that refluxing ureters differ from normal ureters in having disorganized smooth muscle fibres and altered smooth muscle cell structure, leading to incompetence of the valve mechanism (Radmayr et al, 2005).
Primary VUR is considered a genetic and familial disorder. That is clear due to sibling recurrence, parent-child transmission, and twin concordance (Kaefer et al, 2000).
UTI is the commonest presentation for VUR in children (Lee et al, 2009). Other presentations include neonate with a history of antenatal hydronephrosis, accidentally discovered during screening of sibling of patient with reflux. It may be presented by childhood hypertension or CRF (Ardissino et al, 2004).
Voiding cystourethrogram is the standard diagnostic approach, and allows for its grading (Greenbaum and Mesrobian, 2006).
. Radionuclide cystography is an alternative approach in some patients but lacks the ability of reflux grading. Voiding urosonography is a relatively recent method and has a role in follow up of cases, for screening siblings and possibly as the first examination for VUR in girls. DMSA scintigraphy is abnormal in most cases of VUR presented with febrile UTI and together with US may replace VCUG as a first diagnostic approach. VUUG is done only if DMSA and/or US is abnormal (Lee et al, 2009).
As regards the natural history of VUR, it is considered excellent. Spontaneous resolution occurs in majority of cases, especially those having low grade VUR (Williams et al, 2008). Reflux nephropathy (RN) is the dense renal scarring associated with VUR. Renal scarring is acquired due to recurrent UTIs. Congenital renal scarring or better termed hypodysplasia also was reported and mainly affects boys. RN can be complicated with renal hypertension and/or CRD and ESRD (Vasama et al, 2006).
Treatment of VUR is either conservative, or interventional by endoscopic or surgical correction.
Conservative management is indicated in children in whom VUR is not complicated and its resolution is expected (low grade VUR). Continuous antibiotic prophylaxis use is controversial but up till now it is indicated if there is a history of febrile UTI in children younger than one year for VUR of any grade. It is indicated in older children if there is bladder/bowl dysfunction (Peters et al, 2010).
Endoscopic correction of VUR is by injection of a bulking agent below or in the ureteral orifice into the detrusor muscle creating a prominent bulge that uplifts the orifice and serves to augment and elongate the intramural ureter correcting reflux. Up till now, Deflux is the only substance that has FDA approval (Hayn et al, 2008). Excellent results could be achieved for VUR correction of any grade by endoscopic injection of Deflux even in complex cases (Perez-Brayfield et al, 2004).
The surgical objective of ureteral reimplantation is to create a passive flap valve mechanism by making a submucosal tunnel with adequate length–to–ureteral diameter ratio. A ratio of 5:1 has high success rates (Austin and Cooper, 2004).
Surgical correction can be achieved by open intra or extra vesical ureteral reimplantation, or by laparoscopic extravesical or the more recently described vesicoscopic cross-trigonal reimplantation (Jayanthi and Patel, 2008).