Comparative Immunohistochemical Study of Multicystic Dysplastic Kidneys With and Without Obstruction

Etiology of multicystic dysplastic kidney (MCDK) remains unknown. Not all cases are associated with obstruction. We compared by immunohistochemistry 17 cases of MCDK (10 cases with and seven without obstruction) to 17 controls and 20 fetal kidneys. TGF-β was negative in obstructive MCDKs and positive in nonobstructive MCDK. IGF2 was overexpressed in obstructive and underex-pressed in nonobstructive MCDKs. PAX2, BCL-2, and β-catenin were expressed equally in obstructive and nonobstructive dysplasia. TGF-β and IGF2 work by different mechanisms in obstructive and nonobstructive MCDKs, but there are no differences among PAX 2, BCL-2, and β-catenin in obstructive versus nonobstructive dysplasia.