The Pathology of Human Renal Cystic Disease

Abstract

Renal cystic disease comprises a wide group of disorders which may be congenital, acquired, sporadic, or genetically determined. All of these disorders have in common the presence of multiple cysts in the kidney, and this may be a primary disease event and lead to organ dysfunction and end–stage renal failure or cyst formation, may be secondary to other tumor or systemic disorders, and may or may not be symptomatic. Several classification schemes for renal cystic diseases have been proposed and modified in the past, and these will probably continue to be modified as more genetic and pathologic information is gathered. One simplified scheme based on current, although necessarily incomplete, published information is suggested in Table 1. For the purposes of classification, the renal cystic diseases have been separated into those of genetic and nongenetic origin and further subdivided into those entities in which renal cyst formation is the primary disease event and those in which cyst formation is a secondary event associated with a separate genetic syndrome. It appears that cyst formation in the kidney is a common response to genetic mutation, and an understanding of the molecular basis of these events would be of significant importance in potential retardation of cyst enlargement and eventual gene therapy strategies. The ultimate goal of renal cystic disease research is to isolate and identify the gene responsible for each disease. To date, although significant and rapid progress has been made in the area of cystic disease genetics and the chromosome locations of many of these genes have now been determined, few of the genes themselves have actually been cloned or their encoded protein products characterized.