Histopathological Study of Congenital Cystic Kidneys With Special Reference to the Multicystic, Dysplastic Type

Abstract

Ten autopsy cases of congenital cystic kidneys were studied by histopathological examination. Eight cases with dysplastic type revealed immature mesoderm, cartilage, localized tight fibrous tissue, hemangiomatous lesion consisting of arterlo‐capillary‐venous elements, extramedullary hematopoiesis, primitive lymph nodes, adipose tissue, and abundant neural tissue in the kidney as well as cystic lesions. These findings strongly suggest that congenital cystic kidneys of dysplastic type are derived from hamartoma or hamartomatous changes chiefly consisting of mesodermal tissue, most of which corresponds to tissue anomaly and is very close to the aberrant form of Wilms’tumor. The presence of focal fibrosis and lymphoid cell infiltration forming focal renal tissue destruction suggest local disturbance of tissue dmerentiation due to some causal elements. As common feature of this type, it is revealed that the babies show lower weights for their fetal ages and die shortly after birth or are delivered as still birth due to hypoplasia and atelectasis of the pulmonary tissue.

Unilateral and segmental localised polycystic kidney disease

“…1 The cysts of partially diVerentiated Wilm's tumour again are similar but the absence of blastema and immature fetal elements is incompatible with this entity. 2 In segmental cystic dysplasia the nephrons in the septa between cysts are rarely fully formed and are usually associated with metaplastic elements such as cartilage. Despite extensive sampling no such elements were found in this case.…”