The drug of choice for nephrotic syndrome

Kidney disease is quite harmful to human health. People with poor kidneys usually feel tired, have trouble sleeping, and suffer from frequent pain. Nephrotic syndrome is a relatively common disease that is very harmful to the human body, so it must be treated as soon as possible. Currently, nephrotic syndrome is treated with drugs, but some drugs are not very effective. So, what are the drugs of choice for nephrotic syndrome?

1) Thiazide diuretics: They mainly act on the thick-walled segment of the ascending limb of the loop of Henle and the anterior segment of the distal convoluted tubule, causing diuresis by inhibiting the reabsorption of sodium and chloride and increasing potassium excretion. The commonly used medication is hydrochlorothiazide 25 mg, orally 3 times a day. Long-term use should prevent hypokalemia and hyponatremia.

(2) Potassium-retaining diuretics: They mainly act on the posterior segment of the distal convoluted tubule, excreting sodium and chloride but retaining potassium. They are suitable for patients with hypokalemia. The diuretic effect is not significant when used alone, and it can be used in combination with thiazide diuretics. Commonly used medications include triamterene 50 mg, 3 times a day, or the aldosterone antagonist spironolactone 20 mg, 3 times a day. Hyperkalemia must be prevented during long-term use and it should be used with caution in patients with renal insufficiency.

(3) Loop diuretics: They mainly act on the ascending limb of the loop of Henle and have a strong inhibitory effect on the reabsorption of sodium, chloride and potassium. Commonly used medications include furosemide (Lasix) 20-120 mg/d, or bumetanide (buturetanamine) 1-5 mg/d (40 times more potent than furosemide at the same dose), taken orally or intravenously in divided doses. The effect is better when it is given immediately after the use of osmotic diuretics. When using loop diuretics, caution must be exercised to prevent hyponatremia, hypokalemia, and hypochloremia-induced alkali poisoning.

(4) Osmotic diuretics: By transiently increasing the plasma colloidal osmotic pressure, water in the tissues can be reabsorbed into the blood. At the same time, it creates a hyperosmotic state in the renal tubular fluid, reduces the reabsorption of water and sodium, and causes diuresis. Sodium-free dextran 40 (low molecular weight dextran) or hydroxyethyl starch (706 generation plasma, molecular weight of 25,000 to 45,000 Da) is commonly used, 250 to 500 ml intravenous drip once every other day. Subsequent addition of a loop diuretic can enhance the diuretic effect. However, this type of drug should be used with caution in patients with oliguria (urine volume < 400 ml/d), because it can easily form casts together with Tamm-Horsfall protein secreted by the renal tubules and albumin filtered by the glomeruli, blocking the renal tubules. Its hyperosmotic effect can cause degeneration and necrosis of renal tubular epithelial cells, inducing "osmotic nephropathy" and leading to acute renal failure.

(5) Increase plasma colloid osmotic pressure: Intravenous infusion of plasma or human albumin can increase plasma colloid osmotic pressure, promote water reabsorption in tissues and promote diuresis. If followed by immediate intravenous infusion of furosemide 60-120 mg (added to glucose solution and slowly infused intravenously for 1 hour), a good diuretic effect can be achieved. Human albumin can also be considered when the patient has severe hypoproteinemia and malnutrition. However, since the transfused plasma and its products will be excreted in the urine within 24 to 48 hours, plasma products should not be transfused excessively or too frequently. Otherwise, glomerular hyperfiltration and tubular hypermetabolism may cause damage to the glomerular visceral and tubular epithelial cells, which may affect the efficacy of glucocorticoids and delay disease remission in mild cases and damage renal function in severe cases. This diuretic method should be used with caution in patients with heart disease to avoid heart failure induced by acute expansion of blood volume.

6) Others: For patients with severe refractory edema, if the above treatments are ineffective, short-term blood ultrafiltration therapy can be tried. This therapy can quickly dehydrate the patient. For patients with severe ascites, ascites drainage under strict aseptic conditions can be considered, and then the patient can be concentrated in vitro and then reinfused into the vein.

The principle of diuretic treatment for patients with nephrotic syndrome is not to be too fast or too strong, so as not to cause insufficient blood volume, aggravate the tendency of blood hyperviscosity, and induce thrombosis and embolism complications.