In the large white fatty kidney it is the tubular structure which is prin cipally involved—especially the convoluted tubes in the cortex. The kid ney is larger than natural, and its capsule can be readily detached. The cortical part of the kidney, to swelling of which the increase in size is due, is perfectly smooth on the surface and pale in colour. No ramifying ca pillaries are to be seen, but here and there red specks from extravasation of blood dot the anaemic surface.
On section the cortex has the same pallid tint, and contrasts curiously with the cones of the pyramids which still retain their healthy colour. By the microscope the convoluted tubes are seen distended to twice their natural size ; and their epithelial lining is swollen and granular looking. The tubes often contain granular debris and fibrinous exudation, and,. sometimes, extravasated blood from a ruptured Malpighian body.
After a time the epithelial cells in the tubes become disintegrated and are removed, and sometimes increase of the interstitial connective tis sue takes place as in the preceding variety. The kidney then shrinks and may become granular on the surface, but still continues very pale in colour.
Amyloid disease in the kidney is usually associated with the same de generation of the liver and spleen. If the degeneration is marked, the or gan is increased in size and has a waxy, pale, and slightly translucent ap pearance. The amyloid change begins, as a rule, in the vessels of the Malpighian tufts, but soon spreads from these to the vessels (both afferent and efferent), the vascular plexuses (both intertubular and interlobular), and the urinary tubules. This condition is often combined with other forms of renal degeneration.
Symptoms.—The symptoms of acute Bright's disease have been already considered in the chapter on Scarlatina.
The chronic disease in its earlier stages, and until it gives rise to dropsy, is accompanied by few symptoms, and, indeed, is probably often over looked. The child is pale, dull, and listless. He complains of his head, and is capricious in his eating. Sometimes he passes large quantities of water, which—especially if the disease be of the granular variety—may be of normal density, and contain no albumen. Even when dropsy occurs, albuminuria may be absent or trifling.
A little boy, aged one year and ten months, with sixteen teeth, began gradually to get poorly. He grew pale, seemed heavy and sleepy, and
vomited often after his meals. After this state of things had continued for a month his face became puffy, his eyelids swelled, and general cedema appeared over the body and limbs. When taken into the East London Children's Hospital, no disease of any organ could be discovered ; the liver and spleen were of natural size ; the heart was healthy, and the tempera ture was normal. There was no sign of peeling of the skin. For some clays no urine could be collected, for the quantity was scanty, and the child passed it all in his cot. At last some was obtained, but no albumen was discovered, nor could any casts of tubes be seen. Purges and dia phoretics soon dispersed the oedema, and the child then took iron and cod-liver oil. The sickness continued for some weeks after the oedema had disappeared. The urine was examined several times, but no albumen was ever found.
The dropsy in this case was not the result of anaemia and weakness, for the child was not at all emaciated, and his mucous membranes were fairly red. The cedema had all the characters of kidney dropsy. It began in the face, and was distributed very generally over the body. A similar form of dropsy without albuminuria or casts is sometimes found as a sequel of scarlet fever.
In some cases Bright's disease appears to be quite latent Lulli.l cedema occurs.
A little boy, aged twenty-one months, with twelve teeth, came into the hospital, under my care, with slight dropsy which had lasted for a week. The child had never had scarlatina or measles ; and had been a fairly healthy boy, although for some weeks his bowels had been relaxed, and the discharges offensive. He had suffered, shortly before admission, from ulceration of the mouth, which, however, had been soon recovered from. He coughed, and his appetite was poor.
When the child was first seen the oedema, although slight, was gen eral. The urine was scanty and alkaline, and contained one-sixteenth of albumen. There was a deposit of triple phosphate crystals, with many large and small hyaline casts, and some granular casts. The temperature at first was normal, but after a few clays rose to 101.4° ; the child began to cough; he was then violently convulsed, and died a few hours after wards.