Problem description:
What disease could it be?
Analysis:
Please refer to the following solutions.
Normal people filter raw urine as much as 180 liter every day, but only about 1.5 liter is reabsorbed and secreted by renal tubules and finally concentrated and discharged. The content of protein is about 40 ~ 100 mg, which can't be determined by urine protein qualitative method.
Proteinuria is pathological, and there are functional proteinuria and pathological proteinuria. Functional proteinuria, also known as physiological proteinuria, refers to temporary proteinuria in healthy people. More common in young people. Under the influence of strenuous exercise, fever, high temperature, cold, mental stress and other factors, renal vascular spasm or congestion, resulting in increased permeability of glomerular filtration membrane, a large number of protein "escape". Urinary protein in normal pregnant women can be slightly increased, which is related to the increase of renal flow and glomerular filtration rate. Functional proteinuria will disappear automatically after the inducement is eliminated. So it is also called reversible proteinuria or transient proteinuria.
There is a simple and rough test method for whether there is protein in urine and how much protein it contains: When the urine is boiled, white turbidity may appear in the urine. Add 5- 10 drops of 5% acetic acid and boil it. If the turbidity disappears, there is no protein in the urine, and the qualitative test of urine protein is negative; If the turbidity does not disappear, but increases, showing flocculent precipitation or clot, the urine protein qualitative test is positive.
Pathological proteinuria refers to persistent protein in urine caused by pathological changes in a certain system or organ of human body. Generally, the amount of urinary protein in 24 hours exceeds 150 mg. Common in three situations:
Glomeruloproteinuria: damage to glomerular capillary wall caused by various reasons (such as immune damage) reduces or loses the load, resulting in increased glomerular permeability. After filtration, more plasma protein exceeds the reabsorption capacity of renal tubules, resulting in proteinuria. Such as acute and chronic nephritis, lupus nephropathy and diabetic nephropathy.
Renal tubular proteinuria: When renal tubular disease or renal tubular dysfunction occurs, protein reabsorption decreases or protein secretion increases, resulting in increased urinary protein. Such as renal tubular acidosis, nephropathy caused by analgesics and nephrotoxicity of antibiotics.
The urine of patients with overflow proteinuria (also known as coagulative proteinuria) is turbid when heated to 40℃, coagulated at 60℃ and dissolved at 100℃. Common in myeloma, primary amyloidosis and macroglobulinemia.