What is Nephrotic syndrome
The primary degenerative defect in nephrosis is in the capillary basement membrane of the glomerulus. As this degeneration continues, the effect on the tissue is to create large enough "pores" to permit the escape of large amounts of protein into the filtrate. The subsequent tubular changes are probably secondary then to the high-protein concentration in the filtrate with some protein uptake from the tubule lumen. Thus both filtration and reabsorption functions may be disrupted in nephrosis.
Clinical symptoms. The primary symptom in nephrosis is massive albumin in the urine. Other findings include additional protein losses in the urine, including globulins and specialized binding proteins for thyroid and iron. The loss of these proteins sometimes produces signs of hypothyroidism and anemia. Blood levels of plasma proteins drop as a result of this loss, and serum cholesterol levels rise.
As the serum protein losses continue, tissue proteins are broken down in an effort to supply the body’s need, and general malnutrition ensues. Fatty tissue changes in the liver, sodium retention, and edema occur. Severe fluid accumulation in the abdomen and legs may mask the gross tissue wasting that is occurring.
Diet therapy. Treatment is directed toward control of the major symptoms. These include edema, malnutrition, and massive protein losses.
PROTEIN. Replacement of the prolonged nitrogen deficit from the protein loss is a fundamental and immediate need. The plasma albumin level may have been reduced to 20% or less of its normal value. This is the major factor in causing the water retention and resultant tissue swelling. Daily protein allowances of 100 to 150gm. or more will be needed in the diet.
CALORIES. To ensure protein use of tissue synthesis sufficient calories must always be given. High calorie intakes daily of 50 to 60 calories per kilogram of body weight are essential. Every effort must be made to ensure that the patient actually consumes the diet. His appetite is usually poor, so that much encouragement and support are needed. The food must be appetizing and in the form most easily tolerated.
SODIUM. To combat the massive edema sodium levels in the diet must be sufficiently low. Usually the 500 mg. sodium diet is satisfactory to help initiate dieresis.
The dietary management is similar to that given for hepatitis, with even more need for sodium restriction. Use of low-sodium milk is indicated to help maintain the desired high-protein intake and yet restrict sodium to the more severe levels.