Abstract
Purpose: To study the long-term development of urographic renal morphology in adults with vesicoureteral reflux, to investigate the relationship between renal damage and reflux grade, and to analyse the association between the long-term urographic outcome and the occurrence of acute pyelonephritis and reflux during follow-up. The purpose was also to try to distinguish between acquired and developmental renal damage, based on analyses of renal histological specimens and urographic features, and to analyse associated congenital urogenital abnormalities and family history of reflux, reflux nephropathy, urological malformation or death from end-stage renal disease.
Material and Methods: Renal damage was identified in 100 (83 women) of 115 adults, selected because of documented reflux. Eighty-seven patients had two urographies done (median interval 14.3 years). The extent and progression of renal damage were assessed and features of developmental renal damage were determined. Histological renal specimens were available in 23 patients with renal damage.
Results and Conclusions: The extent of renal damage correlated positively with the severity of reflux. No renal damage developed during the follow-up in 45 previously undamaged kidneys and progression of renal damage was rare (4 of 120 previously damaged kidneys), despite persisting reflux in half of the cases and episodes of acute pyelonephritis during follow-up. Thus, repeated renal imaging is rarely justified in adults with reflux nephropathy. Histological examination showed "chronic pyelonephritis" in all 23 cases and co-existing renal dysplasia in 1 case. The detailed urographic analysis did not reveal support for developmental renal damage. High frequencies of associated congenital urogenital abnormalities and of a positive family history were found. Thus, congenital and/or hereditary factors cannot be discarded as background factors for the development of renal damage.