Vesico-ureteric reflux and other risk factors for renal damage: identification of high- and low-risk children

This article reviews the Literature with respect to various risk factors fo r permanent renal damage in children with urinary tract infection. Vesico-u reteric reflux is an important risk factor, but renal damage can occur in t he absence of reflux. Renal damage does not always occur in the presence of gross reflux. Renal scars always develop at the same site as a previous in fection in the kidney. Recurrent pyelonephritis and delay in therapy increa se the likelihood of renal damage, although it is not known how long a dela y is dangerous to the human kidney. Recent studies using (99m)technetium-di mercaptosuccinic acid (DMS A) scintigraphy have not confirmed the findings of previous studies showing that children below 1 y of age are more vulnera ble to renal damage. It is more Likely that all children run the risk of re nal scarring in cases of acute pyelonephritis. The role of bladder pressure is still not entirely understood. Therefore more studies are needed in ord er to determine the relationship between high voiding pressures in some, ot herwise healthy, children with urinary tract infection and renal scarring. The importance of bacterial virulence in the development of renal scarring is unclear. DMSA scintigraphy and voiding cystourethrography are the most r eliable tools for identifying children at risk of renal scarring. As a sing le method DMSA scintigraphy appears to be better than voiding cystourethrog raphy.