What causes less urine?

In real life, some people have the problem of less urine. Even if they drink a lot of water every day, the frequency of urination does not increase. This makes many people worried and afraid, wondering if there is something wrong with their body. There are many reasons for less urine. Generally, people whose urine volume is less than 400 ml in 24 hours may have health problems. For example, acute nephritis, diarrhea and vomiting, heavy bleeding, excessive sweating, etc. are all inducing factors. So what should we do?

Causes and common diseases

1. Prerenal

(1) Decreased effective blood volume. Shock, severe water loss, massive bleeding, nephrotic syndrome, and hepatorenal syndrome caused by various reasons cause a large amount of water to infiltrate the tissue gap and serosal cavity, resulting in decreased blood volume and reduced renal blood flow.

(2) Heart failure due to various reasons resulting from decreased cardiac pumping function, severe arrhythmias, and unstable systemic circulation function after cardiopulmonary resuscitation. A decrease in blood pressure causes a decrease in renal blood flow.

(3) Renal vascular disease: renal vascular stenosis or inflammation, nephrotic syndrome, lupus nephritis, and renal artery embolism and thrombosis caused by long-term bed rest; hypertensive crisis, pregnancy-induced hypertension, etc. cause persistent spasm of the renal artery and renal ischemia leading to acute renal failure.

2. Renal

(1) Glomerular disease Rapidly progressive nephritis and chronic nephritis can cause a sharp deterioration in renal function due to severe infection, persistently high blood pressure, or the effects of nephrotoxic drugs.

(2) Renal tubular disease Acute interstitial nephritis includes drug-induced and infectious interstitial nephritis; acute tubular necrosis caused by biological toxins or heavy metal and chemical toxins; severe pyelonephritis complicated by renal papillary necrosis.

3. Postrenal

(1) Mechanical urinary tract obstruction such as stones, blood clots, necrotic tissue blocking the ureter, bladder inlet and outlet, or posterior urethra.

(2) External pressure on the urinary tract, such as tumors, retroperitoneal lymphoma, idiopathic retroperitoneal fibrosis, and prostatic hypertrophy.

(3) Other ureteral surgeries, scar contracture after healing of tuberculosis or ulcers, renal torsion caused by severe renal ptosis or wandering kidney, neurogenic bladder, etc.

Treatment principles

1. General treatment

Rest in bed, eat properly, and those with renal insufficiency should eat a low-salt, high-protein diet.

2. Treatment of the cause

For prerenal cases, volume expansion is given; for renal cases, improvement of renal circulation and removal of inducing factors are given; for postrenal cases, surgeons are generally asked to relieve obstruction and other treatments.

3. Symptomatic treatment

Maintain electrolyte balance, nutritional support and other treatments.

4. Intake and output monitoring

When vital signs are unstable, ECG monitoring is required.