Renal Dysplasia: A Clinicopathologic Review of Six Cases

ABSTRACT

Renal dysplasia results from aberrant histogenesis in metanephric differentiation. It is characterized morphologically by abnormal organization and a persistence of primitive structures, such as cartilage, undifferentiated mesenchyme, and immature tubules. Six cases of renal dysplasia from five children and one adult are reviewed. Five patients were female and one patient was male. The chief complaint was urinary incontinence in four patients, dysuria in one patient, and the sixth patient suffered from vesicoureteral reflux. No evidence of family history of renal dysplasia in any patient was seen. According to Risdon's classification, three cases were hypoplastic dysplasia, one case was dysplasia in a duplex system, one case was dysplasia in a triplex system, and one case was dysplasia with vesicoureteral reflux. The ipsilateral ectopic ureteral orifice was identified in four patients, two of which drained into a Gartner's duct cyst, and the orifice was suggested in one patient. On histologic examination, all cases showed primitive ducts surrounded by concentrically arranged primitive mesenchyme. Nests of metaplastic cartilage were observed within the stroma in three of the six cases.