Renal scarring

Sheu JN, Chen MC, Cheng SL, Lee 1C, Chen SM, Tsay GJ. Urine interleukin-1 beta in children with acute pyelonephritis and renal scarring. Nephrology (Carlton). 2007 12 487-93. 

Mundi H, Bjorksten B, Svanborg C, Ohman L, Dahlgren C. Extracellular release of reactive oxygen species from human neutrophils upon interaction with Escherichia coli strains causing renal scarring. Infect Immun 1991 59 4168-72. 

Renal scarring secondary to vesicoureteral reflux may be the cause of renovascular hypertension. Renal ablation is an alternative to nephrectomy to remove to involved kidney. The selective embolization should be performed with alcohol to prevent collateral revascularization. The efficacy is debated considering that embolization may delay the definitive treatment [26]. Gelfoam and coils are less valuable than alcohol because of collateral revascularization (Fig. 23.9a,b). 

In children with spontaneous hematuria, US can rule out urolithiasis or tumor. In renal failure, US can exclude renal vein or artery thrombosis (Laplante et al. 1993). Doppler US can confirm diagnosis and help follow-up of hemolytic-uremic syndrome (Patriquin et al. 1989). In children with palpable abdominal mass, US and plain film of the abdomen are usually sufficient to establish the diagnosis, which is then confirmed by enhanced CT or MRI. In patients with arterial hypertension, B-mode US can detect renal scar, hypoplasia, or nephropathy. Then, Doppler examination of renal vessels and parenchyma can orient diagnosis toward vascular cause. Renal angiography remains the reference examination (Garel et al. 1995). 

Power Doppler sonography versus DMSA scintigraphy in acute pyelonephritis and in prediction of renal scarring. J Nucl Med 43 27-32... 

MR urography is superior to DMSA scanning in the evaluation of renal scarring and pyelone-phriti. 

Common indications for Tc-99m DMSA scans include detection of acute pyelonephritis (Figs. 1.3.11,1.3.12) renal scars after UTI detection... 

The junctional parenchymal defect should not be mistaken for a renal scar. The segmental arteries have no collateral circulation. The sonographic appearance of the kidneys for the first 6 months differs from that later in life. 

Vesicoureteral reflux will be present in nearly all patients after bladder closure, thus making antireflux surgery necessary. Pyelonephritis and renal scarring are reported to occur in 25%-50% of patients (Hollowell et al. 1992). 

Chan Y, Chan K, Roebuck D et al (1999) Potential utility of MRI in the evaluation of children at risk of renal scarring. Pediatr Radiol 29 856-862... 

Noe HN, Wyatt RJ, Peden JH et al (1992) The transmission of VUR from parent to child. J Urol 148 1869-1871 Olbing H, Clagsson 1, Ebel K et al (1992) Renal scars and parenchymal thinning in children with VUR. J Urol 148 1653-1656... 

Stokland E, Hellstrom M, Jakobsson B et al (1999) Imaging of renal scarring. Acta Pediatr Scand 431 [Suppl] 13-21... 

Nonneurogenic neurogenic bladder or the so-called Hinman syndrome is at the extreme end of the spectrum of nonneurogenic bladder-sphincter dysfunction. This syndrome shows severe clinical manifestations including urinary retention, severe bladder-sphincter dysfunction, VUR, hydronephrosis and hydroureter and renal scarring. 

Of greatest importance is the observation by Naseer and Steinhardt (1997) who, in their study on 538 patients with a history of daytime urinary incontinence, identified 51 children with VUR, UTI and dysfunctional voiding in whom new renal scars had developed while they were under care. They concluded that voiding dysfunction is a significant risk factor not only for UTI and VUR development and perpetuation, but also for the development of new renal scars when associated with infection and VUR. An association between urinary tract dysfunction and reflux nephropathy was also demonstrated by Nielsen (1984). 

Naseer SR, Steinhardt GF (1997) New renal scars in children with urinary tract infections, vesicoureteral reflux and voiding dysfunction a prospective evaluation. J Urol 158 566-568... 

Fig. 15.17a,b. Cystic pyelitis and ureteritis, a IVU bilateral renal scars and cyst-like filling defects at the level of the collecting systems (especially the right ureter), b Corresponding US of the right kidney (RK) transverse scan, marked multilayered thickening of the renal... 

Renal scars are the most feared complications of APN since they may induce complications later in life. 

The topic of UTI remains controversial and the disease is not completely understood. However, the current imaging and therapeutic approach seems successful at least in terms of lowering the risk of renal scarring and late complications. 

Brook I (1994) The role of anaerobic bacteria in perinephric and renal abscesses in children. Pediatrics 93 261-264 Chambers T (1997) An essay on the consequences of childhood UTI. Pediatr Nephrol 11 178-179 Chan Y, Chan K, Yeung C et al (1999) Potential utility of MRI in the evaluation of children at risk of renal scarring. Pediatr Radiol 29 856-862... 

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