CHRONIC NEPHRITIS (BRIGHT’S DISEASE)
Chronic nephritis may develop as a sequel to an acute attack, and an individual suffering from chronic nephritis may at any time develop acute symptoms. In any case the dietetic treatment would necessarily have to be made to cover the existing symptoms.
Dietetic Treatment.—In cases where the patient has entirely recovered from uremia but still manifests symptoms of water and salt retention, the diet would be naturally directed to cover the latter, at the same time taking care not to strain the weakened functions by giving more food than could be readily handled. The water and salts still have to be restricted, but a certain amount of fat and carbohydrate with small additions of nitrogenous food materials may be added from time to time as the kidneys show improvement. It must be borne in mind, however, that at this time it is very easy to overtax the renal organs and it is safer to err on the side of under rather than over feeding.
The logical treatment, therefore, consists of utilizing the improved functions while those still failing to react are getting further rest.
Adjusting the Proteins in Diet.—If the individual shows a definite anemia, as is often the case after acute attacks, either as a result of the disease itself or the necessarily low diet, which the acute symptoms of uremia and edema made necessary, other measures are necessary to bring the body back to a normal condition. It has been found that in these cases where there has been no permanent damage to the renal organs, but merely a temporary impairment of the functioning power, the treatment must be, first, a rest to the affected parts; second, the temporary restriction of all articles of food which impose a tax on the kidneys to eliminate; the third, the gradual return to normal diet as the acute symptoms decrease and the function of the kidneys no longer shows impairment. Such a case is cited by Strouse and Perry[127] as occurring in the Michael Reese Hospital. Mr. X. recovered from the acute stage of nephritis and all signs of edema and uremia disappeared; the man was kept on a low salt and low protein diet for a long time. His urine was clearing up, but he did not feel up to standard and remained anemic. Thinking in all probability that his symptoms were due to a low protein diet, meat was slowly added to his dietary until he was receiving 60 grams of protein a day. There was an immediate general improvement in his condition with no increased renal disturbance. It is an obvious fact that chronic nephritis, like any other chronic condition, requires a different method of treatment from that practised to relieve the acute stage. The very fact that it is chronic proves that the strenuous methods are neither necessary nor wise.
Testing the Kidney Functions.—The authorities of to-day endeavor to ascertain the extent of the damage to the renal organ by testing its functioning power. These renal function tests have been the subject of much interest and investigation. Probably the ones most commonly employed are those devised by Hedinger and Schlayer[128] and adapted for use in the Johns Hopkins Hospital by Mosenthal.
Diets Used in Tests.—The diet employed in making these tests consists of different amounts of certain substances known to be diuretic in character. This diet is rigidly adhered to and a careful analysis of the urine passed, the total quantity and specific gravity of each specimen made and in this way the various functions of the kidneys and the impairment thereof are tested. Thus an intelligent adjustment of the diet may be made.
Renal Functional Tests.—The following schedule is used by Mosenthal, of the Johns Hopkins Hospital, in making what is known as the “Two-Hour Test for Renal Function”:
HEDINGER-SCHLAYER-MOSENTHAL DIET[129]
| For | Date |
All foods to be salt-free from the diet kitchen, salt for each meal will be furnished in weighed amounts.[130]
All foods or fluids not taken must be weighed or measured after each meal and charted in spaces below. Allow no food or fluid at any time except at meal times.
Note any mishaps or irregularities that occur in giving the diet or collecting the specimens.
8 A.M. No food or fluid is to be given during the night or until 8 o’clock next morning (after voiding) when the regular diet is resumed.
Patient is to empty bladder at 8 A.M. and at the end of each period as indicated below. The specimens are to be collected for the following periods in properly labeled bottles:
8 A.M. to 10 A.M.; 10 A.M. to 12 Noon; 12 Noon to 2 P.M.; 2 P.M. to 4 P.M.; 4 P.M. to 6 P.M.; 6 P.M. to 8 P.M.; 8 P.M. to 8 A.M.
Chart Used in Johns Hopkins Hospital.—The following chart is inserted here to show the method used in the Johns Hopkins Hospital for carrying out the Two-hour Renal Test:
| Time of Day | Urine | NaCl | Nitrogen | |||
| C.C. | Specific Gravity | Per cent | Grams | Per cent | Grams | |
| 8 A.M.-10 A.M. | ||||||
| 10 A.M.-12 Noon | ||||||
| 12 Noon-2 P.M. | ||||||
| 2 P.M.-4 P.M. | ||||||
| 4 P.M.-6 P.M. | ||||||
| 6 P.M.-8 P.M. | ||||||
| 8 P.M.-8 A.M. | ||||||
| Total day | ||||||
| Night, 8 P.M. to 8 A.M. | ||||||
| Total 24 hours | ||||||
| Intake of fluid | ||||||
| NaCl | ||||||
Urine to be collected punctually every two hours and kept in the ice-box, every specimen having twenty drops of tutuol added to insure preservation.
Another modification of the Hedinger-Schlayer diet is used in the Peter Bent Brigham Hospital,[131] Boston, Massachusetts, as follows:
| 7 A.M. | Coffee, milk, sugar, toast, and butter. |
| 10 A.M. | Milk, toast, and butter. |
| 12:30 P.M. | Bouillon, broiled steak, butter, mashed potatoes, toast, coffee, milk, sugar. |
| 4 P.M. | Tea, milk, sugar, crackers. |
| 7 P.M. | Soft egg, blanc-mange (1 egg, sugar, cornstarch, and milk) and cream. Amounts sufficient to give 2500 calories, 1500 c.c. fluid, 76 grams of protein, 127 grams of fat, 245 grams of carbohydrate, and from 5 to 8 grams of sodium chloride. |
On two days previous to the test the patient usually had a diet containing 2000 calories, 75 grams of protein, 4 grams of sodium chloride.
The test diet is a mixed diet containing known amounts of water, nitrogen, and chloride, together with the food diuretics (purins, salt, and water), as can be seen. The diet is divided into unequal portions containing known but varying amounts of fluid, nitrogen, and salt. Two-hour specimens are collected from 7 A.M. to 9 P.M., and one night specimen is obtained containing all the urine passed between 9 P.M. and 7 A.M. Each specimen is analyzed for volume, specific gravity, total nitrogen, nitrogen concentration, total chloride, and chloride concentration.
Purpose of Tests.—The purpose of the test is to find out to what extent and in what manner the diseased kidney under stimulation by the various diuretics taken in the food reacts in putting out the varying amounts of salt.
Dr. O’Hara likewise describes another test known as The Added Urea and Salt Test, which was first described by von Monakow and also carried out in the Peter Bent Brigham Hospital. The method used was as follows: