Causes

The influence of overeating and of injudicious eating in producing chronic nephritis is so generally appreciated that it scarcely needs discussion. Chronic diffuse nephritis, like acute nephritis, is oftenest due to infection. It sometimes grows out of acute nephritis, or is produced by the same infectious diseases, or it arises from chronic suppuration, malaria, and syphilis. Formad's statistics have made it evident that it is this form of nephritis that the prolonged and excessive use of alcoholic beverages produces. They provoke albuminuria by exciting structural changes in the glomeruli, and even before they cause it they often cause casts to appear in the urine by perverting the secretions of the renal epithelium or by destroying its cells. Nephritis in a drunkard is, however, due in part to the deranged condition of stomach and bowels, and only in part to alcohol directly.

Treatment

In chronic diffuse nephritis there are the same indications for a milk diet as in acute nephritis. It is, however, so prolonged a sickness that an exclusive milk diet cannot be maintained continuously. When acute exacerbations occur, as they often do, a milk diet for a short time is as necessary as in acute nephritis. Although a strict milk diet has been commended, and by some clinicians urged as a necessity in these cases, there is evidence that some patients do not do so well upon it as when a more varied diet is permitted.

An exclusive milk diet may advantageously be prescribed intermittently in some instances, milk alone being taken for two or three weeks, then a modified milk course or mixed diet for a like time. The numerous mild cases of chronic diffuse nephritis can best use what may be called a modified milk diet or a carefully selected mixed diet. By a modified milk diet, I mean one of which the basis is milk, and from which meats, fish, and eggs are excluded, while bread, starches, fruits, and vegetables form a part. By a selected mixed diet I mean one that contains meats, eggs, and fish, but only a prescribed amount of selected kinds of meat and fish. Breads, gruels, and the most digestible flour products are permissible. The use of butter and cream is to be recommended. Potatoes, peas, beans, and green vegetables in general may be eaten, as may fruit jellies, compotes, and fruits. Some clinicians forbid cabbage, sauer-kraut, asparagus, spinach, and artichokes because of the large amount of potassium that they contain. Rhubarb, sorrel, and tomatoes are also forbidden, because of the oxalates that are in them. Oxalates, however, are less likely to cause trouble in diffuse, than in interstitial nephritis.

Bouillon, meat extracts, and meats rich in extractives, such as beef, must be forbidden, because of the toxins in them or easily generated by them.

There is much difference of opinion as to the availability of different albuminous foods in this disease. Egg-albumen is the least harmful of any. Tessier contrasts their effect on cases of albuminuria in this way: "Fish which is not quite fresh and a little of cheese will cause albumin to reappear when two to four eggs and a slice of ham will not."

Next in degree of innocuity can be placed squab, breast of chicken, ham, cold pork, and lamb. The effect of fish upon albuminuria is disputed. It is probable that the difference of opinion is due to the varying qualities of the fish experimented with. They quickly change when killed, and neither odor nor taste always reveals their condition. If perfectly fresh, they are probably as harmless as any meat. If they are ever so slightly tainted, they contain renal irritants. Oysters and frogs' legs are also permissible. Gelatinous food, such as pig's feet and calves' brain, is harmless. Beef, mutton, game, probably veal, cheese, and the coarser fish, such as salmon, sturgeon, and lobster, must be forbidden. In general, salt and smoked meats ought to be proscribed. Ham is an exception to this rule. Meats should not be fried, but broiled or boiled.

Edema is often an early and very persistent symptom in chronic diffuse nephritis. Rest in bed, so long as it last, cannot therefore be established as a rule, as in acute nephritis. Gentle exercise with rest in the recumbent position from time to time is more likely to maintain a fair degree of health, but when edema is great, rest must be insisted upon. A diet from which common salt is excluded and purgatives facilitate the disappearance of dropsy with the greatest certainty. Milk which contains all of the ingredients needed for the maintenance of life, has in it a minimum amount of salt, but milk must be prescribed in small quantities, not more than six glasses daily at first. When improvement is established fruits also can be permitted. Later when edema is almost or quite gone, breads, rice and cereals prepared without salt, and custards or raw eggs can be added to the foods already prescribed. Such management often will effect the removal of dropsy. In other cases the fluid must be drained from the edematous tissues through incisions made at the ankles or through trocars inserted into the swollen legs. A diet free from salt or relatively so will help greatly to prevent its prompt reaccumulation.

During the inclement months of the year a residence in mild and warm climates should be advised. A winter in Egypt, Florida, California, southwestern Texas, or Arizona is especially beneficial. The sufferer is able in these places to be out-of-doors and to obtain the tonic effect of fresh air and sunshine. In Egypt or Arizona, and to a less extent in California and Texas, the dryness of the air will promote rapid exhalation of moisture from the lungs and skin, and will tend to diminish, or at least to prevent rapid increase of edema.

Daily rubbing of the skin with a woolen cloth or rough towel does good. If there are uremic symptoms, hot baths must be taken. The greatest care must be exercised to protect the skin against cold.

The bowels must be well and regularly emptied in mild cases. More copious, even drastic, purgation may be needed in some instances, especially when edema exists or uremia threatens or exists.

A residence at spas often does good. The change of scene, and of mode of living, and the greater amount of out-of-door life are helpful. The best waters are those that are purest and freest from mineral matter. For certain patients a slightly laxative saline water is good. As a rule, the best effect of the water is obtained from the quantity of it that is drunk rather than from mineral ingredients in it. The waters of the Waukesha Springs of Wisconsin and of the Poland Springs of Maine are therefore among the best because they contain so little mineral matter.