Pyelonephrosis is an enlargement of the renal pelvis and calyces accompanied by atrophy of the renal tissue due to urinary tract obstruction. Urinary tract obstruction can occur anywhere in the urinary tract, either unilaterally or bilaterally. The degree of obstruction can be complete or incomplete and can cause hydronephrosis after a certain period of time. If there is a narrowing or obstruction in any part of the urinary tract and normal neuromuscular dysfunction, the passage of urine can become obstructed, resulting in urinary flow obstruction. The pressure in the part above the obstruction gradually increases due to poor urine discharge, and the lumen expands, eventually leading to hydronephrosis, expansion, thinning of the renal parenchyma, and decreased renal function. Dietary care for the phenomenon of hydronephrosis: 1. Daily diet of hydronephrosis pay attention to eat as little or no salty and high-protein stuff. For example, more salt, eggs, potatoes, soybeans, etc., can be appropriate to eat white radish and honey and other foods that are conducive to unblock waterways. 2, do not eat fried, pickled food, cola, burgers, milk, sugar, nuts, beans, meat dishes, etc.. Drink more water (this article must be done, provided that it is not edema, after edema changed to 80% of urine), can eat rice, coarse grains. But the dishes should be mainly green vegetables, meals with green vegetables, other vegetables as a supplement. 3, increase energy intake, but in order to avoid increasing the burden on the hydronephrosis kidneys, should not eat too much protein-rich food. Energy intake mainly relies on carbohydrates and fatty foods. If you have unilateral hydronephrosis, you do not need to limit the amount of water you drink. If you have bilateral hydronephrosis and renal dysfunction, you should limit the daily water intake. 4, avoid eating beans and their products (such as tofu, bean sprouts, bean flour, etc.). 5.People with edema, hypertension and heart failure should eat a diet with less salt or no salt. 6. Eat a light diet, avoid alcohol and spicy food, and eat less greasy and fishy food containing animal protein (such as fatty meat, shrimp, crab, etc.). 7. Restrict sodium diet. Supplement sufficient heat, but do not restrict protein, should be mainly high-quality protein, but the appearance of azotemia kidney function impairment symptoms, should limit protein diet.