FIGURE 3.

A, This case of segmental hypoplasia from a 2-year-old shows a hypoplastic focus. Notice that the focus is bordered on each side by normal-appearing cortex. The focus is devoid of glomeruli, both intact and sclerotic. It contains large dilated veins, a few tubules, loose connective tissue stroma, and a focus of lymphoid inflammation. Medullary tissue is visible at the bottom of the image. It consists of collecting ducts and cellular stroma. No loops of Henle are present. B, This case of segmental hypoplasia from a 33-year-old shows another hypoplastic focus. The focus is bordered on the left by normal-appearing cortex. The focus itself is devoid of glomeruli, both intact and sclerotic. It contains a large dilated vein, a few tubules, loose connective tissue stroma and several foci of adipocytes. C, This case of segmental hypoplasia from a 22-year-old shows another hypoplastic focus bordered on the right by normal-appearing cortex. The focus itself is devoid of glomeruli, both intact and sclerotic. It contains large dilated veins and loose connective tissue. A few small immature-appearing tubules are noted in the subcapsular region. D, This case of segmental hypoplasia from a 22-year-old shows a distorted appearing hypoplastic focus bordered by normal-appearing cortex on each side. The presumed cortical tissue is on the right side of the hypoplastic focus. On the left side is an oval nodule of rudimentary medullary tissue. To its left is a large artery and large dilated vein.