Reflux nephropathy

Abstract

Vesicoureteral reflux associated with abnormalities of the renal parenchyma is called reflux nephropathy. This often results in renal scarring following acute pyelonephritis, and can lead to congenital hypoplastic/dysplastic kidneys due to renal parenchymal lesions. The prognosis of renal function is dependent upon the amount of renal parenchyma that is affected by these lesions. In the case of multiple renal parenchymal lesions in both kidneys, there is a risk of progression to end-stage renal disease. Similarly, there is a decrease in the number of glomeruli, and significant glomerular hypertrophy develops within the residual parenchyma. On the other hand, progression from early-stage to end-stage renal disease due to clinical abnormalities such as renal function deterioration or proteinuria is rare. Therefore, it is necessary for any reflux nephropathy patient with a renal scar to be carefully observed so that progression can be halted if it begins to develop. In addition, hypertension develops in the setting of renin dependence only when the renal function declines and proteinuria has considerably progressed. The reason why the deterioration in renal function is only slight at the early stages of progression is that there is a renal functional reserve. This renal functional reserve remains until + 4SD glomerular hypertrophy. However, this reserve function is completely lost in patients with extreme glomerular hypertrophy of more than + 4SD. Therefore, it is thought that such renal function deterioration progresses slowly in the early stages, but progresses rapidly once such a decline has begun. It is therefore necessary to closely observe patients for reflux nephropathy with the potential to progress to end-stage renal disease, and the development of a febrile urinary tract infection must be treated immediately. Renal function must be preserved by aggressive and immediate treatment of any hypertension and proteinuria, so that progression to end-stage renal disease can be prevented.