What are the causes of increased urine volume?

Urinating is something our bodies have to do and we have to do it. The purpose of urination is to excrete excess water and metabolic products from our body. This is actually a very normal thing, but due to some special reasons in our daily life, our body will have an increased amount of urine. So what are the reasons for the increased urine volume?

reason:

1. Endocrine and metabolic diseases

(1) Diabetes insipidus: Due to hypothalamic-neuropituitary dysfunction, the secretion of antidiuretic hormone decreases, causing the renal tubular reabsorption function to decrease and causing polyuria.

(2) Diabetes: Due to high blood sugar, a large amount of sugar is excreted in the urine, which can cause solute diuresis; due to high blood sugar, the body increases the amount of water intake in order to metabolize and dilute the blood, causing polyuria.

(3) Potassium deficiency: In primary aldosteronism, due to hypothalamic-neuropituitary function, antidiuretic hormone secretion is too low, and the patient shows extreme thirst and polydipsia (daily water intake is more than 4 liters). Polyuria causes water loss, and as the urine volume increases, potassium loss in the urine increases, causing refractory hypokalemia. Urine volume increases and urine specific gravity is below 1.006. Long-term hypokalemia secondary to various reasons can cause renal tubular vacuolar degeneration or even tubular necrosis, which is called potassium-losing nephropathy. Renal tubular potassium reabsorption is impaired, and a large amount of potassium is lost in the urine. Patients show thirst and polyuria, and laboratory tests show impaired tubular function in addition to hypokalemia.

(4) Hypercalcemia: In cases of hyperparathyroidism or multiple myeloma, elevated blood calcium levels damage the renal tubules, causing a decrease in their reabsorption function and resulting in polyuria. It is also prone to the formation of urinary stones, which further damages renal tubular function and worsens the condition.

2. Polyuria caused by kidney disease

(1) Renal polyuria: There is a history of kidney disease and abnormal results in renal function tests, especially those of renal tubular function.

(2) Acute renal failure: Generally, a polyuria phase occurs after the oliguria or anuria phase of acute renal failure. Its characteristics include decreased renal function and prone to electrolyte imbalance.

(3) Chronic renal failure: In the early stages of chronic renal failure, polyuria (mainly increased nocturia) is often present, with urine specific gravity often ranging from 1.010 to 1.012, low urine osmotic pressure, and a flat curve on the radionuclide renal graph.

3. Solute polyuria

Mannitol and sorbitol are needed for treatment. Hyperglycemia may cause polyuria, which will be more obvious if diuretics are used at the same time.

4. Others

Drinking large amounts of water, tea, eating too much salty food or eating too much sugar can also lead to polyuria.