Cystic diseases of the kidney: a perspective on medullary cystic disease.

Fifty-two cases of adequately documented cystic disease of the renal medulla (CDRM) were selected from available literature and analyzed for hereditary mode, age at onset, and duration. In 17, recessively inherited disease appeared at 9.4+/- 1.6(SE) and lasted 7.2+/- 1.7 years while in 21, dominantly inherited disease appeared at 29.3 +/- 2.3 and lasted 2.4+/- 0.4 years. In 14 isolated cases similar data were intermediate. These findings support an hypothesis that at least two genotypes are responsible for the phenotypic expression of CDRM.