MORBID ANATOMY - CHRONIC PRODUCTIVE NEPHRITIS WITHOUT The Kidneys.—The larger number of the affected organs are found after death to be diminished in size; the two kidneys together may not weigh more than two ounces. The capsules are adherent; the surfaces of the kidneys are roughened or nodular, the cortex is thin and of a red or gray color.
A considerable number of these kidneys, however, do not differ in their size or appearance from normal kidneys, except that their capsules are adherent and their surfaces roughened.
Occasionally the kidneys are large, weighing together from 16 to 32 ounces, with smooth or nodular surfaces, and a cortex of red, gray, or white color.
If the nephritis follows chronic congestion, the kidneys remain hard, but the cortex becomes thinned, the capsules adherent, and the surface roughened.
There is a growth of new connective tissue in the cortex and also in the pyramids, which becomes more and more extensive as the dis ease goes on. In the cortex the new tissue follows the distribution of the normal subcapsular areas of connective tissue, is in the form of irregular masses, or is distributed diffusely between the tubes. In the pyramids the growth of new connective tissue is diffuse.
The lobes, both in the cortex and pyramids, undergo marked changes. Those included in the masses of connective tissue are diminished in size, their epithelium is flattened, some contain cast matter, many are obliterated. The tubes between the masses of new
connective tissue are more or less dilated; their epithelium is flat tened, cuboidal, swollen, degenerated, or fatty. The dilatation of the tubes may reach such a point as to form cysts of some size, which contain fluid, or coagulated matter. These cysts follow the lines of systems of tubes, or are situated near the capsules.
- Of the glomeruli a certain number remain of normal size, but with the tuft cells swollen or multiplied. Many others are found in all stages of atrophy and of change into connective tissue. The atrophy seems to depend partly on the growth of tuft cells and intra-capillary cells, partly on the thickening of the capsules, partly on the occlusion of the arteries. If the chronic nepluitis follows chronic congestion of the kidneys the glomeruli remain large, with an increased growth of tuft cells, or they become atrophied, but with the dilatation of the capillaries still evident. The capillaries of the glomeruli may be the seat of waxy degeneration. The arteries exhibit the same changes as have already been described in speaking of chronic exudative nephritis.