Alcohol is probably inadvisable in all forms of chronic Bright's disease, at any rate as a routine. It may be necessary from time to time to order small quantities as a cardiac stimulant, possibly sometimes as a soporific, and in a few instances it may be necessary for the patients to take small quantities with their meals, more especially in the chronic renal disease of the elderly. It is often difficult to carry out these principles inasmuch as many of these patients have been accustomed to take alcohol, often in large quantities and for long periods, but it is very harmful in chronic renal disease for many reasons, and more especially from the effects of alcohol as an excitant of the circulation when it is remembered what extensive cardio-vascular lesions are so often present in chronic renal disease. If alcohol be given at all it must be freely diluted, and this is probably more important than the particular form of alcohol prescribed. The evil effects liable to be produced by alcoholic stimulants in this disease, and for the matter of that in many others, are probably mainly dependent on the actual amount of alcohol in the particular drink consumed. The light wines are more advantageous than the heavier ones for the reason that they contain a less percentage of alcohol. For many years gin has been held in repute as a suitable form of alcohol in renal disease; this is very doubtful and probably owes its origin to its diuretic action which it shares in common with other alcoholic drinks, although perhaps to a somewhat greater extent. If spirits are taken at all they should be freely diluted, and it is essential that only small quantities should be given.
The use of tea and coffee in chronic renal disease is often forbidden owing to the diuretic action of the active principles of tea and coffee. This is done on the general principles that it is inadvisable to stimulate a damaged organ. On the other hand it must be remembered that in chronic renal disease the lesions in the kidney are not uniformly distributed and that not uncommonly considerable areas of the kidney present comparatively little pathological change. Further, the use of diuretics, especially citrate of caffein, is sometimes followed by very beneficial results in cases where dropsy is marked. Both tea and coffee have a very considerable diuretic action and there does not seem really to be any valid objection to their use in cases of chronic renal disease in the absence of gastro-intestinal or uraemic complications. Certainly the mere presence of dropsy should not be regarded as an objection. Coffee is perhaps superior to tea not only from the fact that more milk is taken with it, but also since it produces a less injurious action on the stomach.
There is a variety of chronic nephritis that is associated with syphilis and this form of the disease frequently does not require such rigid dieting as the more ordinary forms of chronic Bright's disease. In the syphilitic variety one of the main characteristics is an intense albuminuria and such patients may present few symptoms of illness beyond general weakness. In some instances even this is not well marked, and were it not for the intense albuminuria the condition might escape observation. This albuminuria is not only very marked in amount, but is often of prolonged duration lasting many months. In some instances dropsy and the other accompaniments of renal disease may be present, and where this is the case the diet should be similar to that ordered in other forms of chronic nephritis. In the large group of cases where the sole manifestation is an intense albuminuria with no signs of uraemia, no dropsy, and no obvious cardio-vascular involvement the less strict diet is more advisable and such patients improve more rapidly if they are allowed a mixed diet containing moderate quantities of meat.
The nephritis of pregnancy unless complications are present also scarcely requires a very rigid diet as here also the course of the disease is often favourable so soon as delivery takes place or the uterus is emptied.
Where the nephritis of pregnancy is of a severe type and accompanied by eclamptic or uraemic phenomena the diet must be similar to that suitable for acute and sub-acute nephritis.
The last group of cases that merits consideration is that in which an albuminuria persists after an attack of nephritis. In many of these cases there are no marked symptoms of renal disease beyond the presence of a persistent albuminuria and casts. Many of these cases are looked upon as examples of chronic nephritis, and no doubt this is correct if the words are used in the sense that an organic lesion of the kidney is present. Such a lesion, however, is not necessarily progressive, and such patients may live for years, sometimes even forty years, excreting all the time a more or less highly albuminous urine, but without presenting any persistent dropsy or any cardio-vascular degeneration, or any uraemic symptoms. In the absence of these complications, no beneficial results will be obtained by putting these patients on a restricted and rigid diet with the idea of thereby diminishing the albuminuria. In fact, much harm may be done by lowering their general health by a milk diet insisted on for too prolonged a time. Doubtless the efficiency of the kidney in these cases is somewhat impaired, but the albuminuria may be regarded rather as produced by a lesion that is the result of the attack of the nephritis, than as the result of a slowly progressive and destructive kidney lesion. There is no class of cases of renal disease where it is more important to diet the patient on general considerations, and such patients should be ordered a simple mixed diet with plenty of vegetables, fruit, and a moderate quantity of fish and meat.