Abstract
As part of a study of experimental vesicoureteric reflux 20 pigs were allocated into five groups according to the presence of reflux, infravesical obstruction and urinary tract infection. The pigs were followed for 20 weeks and thereafter the pathology of the kidneys were studied. It was confirmed that reflux and urinary tract infection produce reflux nephropathy and that the most severe lesions were found in case of dilatation of the upper urinary tract due to infravesical obstruction. It was also substantiated that sterile reflux in case of infravesical obstruction with pronounced dilatation of the upper urinary tract can produce reflux nephropathy.