What Is the Relationship Between Hypertension and Proteinuria?

The presence of protein in the urine is called proteinuria, also known as urinary protein. Normal urine contains a small amount of small-molecule protein, which cannot be detected by routine urine tests. When the protein in urine increases, regular urine tests can detect proteinuria. Proteinuria is a common manifestation of kidney disease, and proteinuria can also occur in systemic diseases.

Basic Information

nickname: Proteinuria
English name: proteinuria
Visiting department: Nephrology, Cardiology, Endocrinology

Common causes: Proteinuria is closely related to kidney disease and can be functional
Common symptoms: Foamy urine, edema, high blood pressure, polyuria, hematuria, etc.

Causes of urinary protein

There are many reasons that can cause proteinuria. They include: functional proteinuria, orthostatic proteinuria, or pathological proteinuria. Frequently there are: extreme periods of fever after intense exercise, eating a high protein diet; nutcracker phenomenon; various kidney diseases and renal vascular diseases.

Clinical manifestations of urinary protein

The clinical manifestations of low back pain caused by different causes are different, for example:

Functional proteinuria

Functional proteinuria is a mild (24-hour urinary protein quantification generally does not exceed 0.5 to 1 g), temporary proteinuria, proteinuria disappears quickly after removal of the cause. It often occurs in young adults, and can be seen in mental stress, severe cold or heat, long marches, physical exertion, congestive heart failure, and high protein diet.

2. Orthostatic proteinuria

Urine protein is absent in the morning, and proteinuria gradually appears after getting up. When standing, walking, or strengthening the lordosis, the protein content of urine increases. The content of urine protein decreases or disappears after resting for 1 hour in the supine position. Youth or adult of size. Repeated orthostatic proteinuria requires attention to exclude renal diseases such as the nutcracker phenomenon (also known as left renal vein compression syndrome, which is caused by the aorta and superior mesenteric artery squeezing the left renal vein).

3. Pathological proteinuria

Proteinuria persists, and there is a lot of protein in urine. Routine urine tests often include hematuria, leukocyte urine, and cast urine. It may be accompanied by other manifestations of kidney disease, such as hypertension and edema. Pathological proteinuria is mainly found in various glomeruli, tubulointerstitial disease, hereditary kidney disease, renal vascular disease and other kidney diseases. Common examples are:

(1) Primary glomerular disease Nephritis can be occult, acute, rapid or chronic. Often associated with hematuria, hypertension and edema. The 24-hour urinary protein in nephrotic syndrome is greater than or equal to 3.5 grams, accompanied by a decrease in albumin, edema, and hyperlipidemia. Renal insufficiency is divided into acute and chronic renal insufficiency. Proteinuria is a manifestation of kidney damage.

(2) Secondary glomerular disease Lupus nephritis is a manifestation of systemic lupus erythematosus involving the kidneys. More common in women of childbearing age. Depending on the severity of kidney involvement, the amount of urinary protein can range from small to large. Purpuric nephritis is a manifestation of renal involvement in allergic purpura. Mainly manifested as hematuria, proteinuria, more common in children, adults can also occur. Proteinuria occurs mostly 2 to 4 weeks after the appearance of purpura. Diabetic nephropathy is a common complication of diabetes. Early renal involvement, but urine protein can be negative in routine urine tests. Microalbuminuria gradually develops and then develops into a large amount of proteinuria. Even end-stage renal disease, that is, renal failure requires dialysis Wait for treatment. Gouty nephropathy urinalysis abnormalities appeared late and mild, only mild proteinuria and a few red blood cells were seen. It can progress to chronic renal failure at an advanced stage. Hypertensive nephropathy The kidney and other damage often occur 5 to 10 years after the occurrence of essential hypertension. The proteinuria caused by benign hypertension is generally mild to moderate urinary protein (24-hour urinary protein is generally not more than 1.5 to 2 grams), and a large amount of proteinuria rarely occurs. Some patients with microscopic hematuria often have hypertension left ventricular hypertrophy, cerebral arterial and retinal arteriosclerosis. Another type of malignant hypertension caused proteinuria is often sudden, 24 hours urine protein quantification can be from small to large, most of which are accompanied by hematuria and leukocyte urine, and renal function is much worse.

(3) Tubulointerstitial diseases such as pyelonephritis, interstitial nephritis, etc., the urine protein is mostly + to ++, and the 24-hour urine protein is more than 2 grams.

(4) Hereditary nephropathy such as Alport syndrome, Fabry disease, thin basement membrane nephropathy, congenital nephropathy syndrome, etc., due to genetic abnormalities, lead to structural defects in the kidneys, leading to varying degrees of proteinuria.

(5) Others such as plateau proteinuria can be seen in people who enter the plateau and stay in the plateau. The urine protein is positive and the amount is> 400 mg / 24 hours. There is no proteinuria before going to the plateau. Back to normal.

Urine protein test

Urine protein tests are divided into qualitative, quantitative and special tests:

Qualitative inspection

Urine routine is best to urinate for the first time in the morning, morning urine is the strongest, and orthostatic proteinuria can be ruled out. When taking a urine sample, discard the first paragraph and retain the middle section of urine. The qualitative examination is only a preliminary screening examination. The diagnosis of renal disease, observation of the condition, and determination of curative effect should be further examined quantitatively.

2. Quantitative inspection

24-hour urine protein quantification, accurately retain the 24-hour urine protein, mix well, and take a urine sample for inspection.

3. Special inspection

Such as urinary protein electrophoresis, urinary light chain quantification, urinary B-ultrasound, renal biopsy, pathological examination, etc., need to be checked according to clinical diagnosis and treatment needs.

Urinary protein diagnosis

Based on proteinuria, combined with edema, hypertension, diabetes, allergic purpura, gout, use of kidney damage drugs and family history, combined with physical examination, such as pleural and ascites fluid, anemia, heart, liver and kidney conditions, fundus examination, etc. The results of various inspections to diagnose.

Urinary protein therapy

Corresponding treatment according to different causes.

Urinary protein prevention

Usually pay attention to avoid too high protein diet. Regular physical examination, if early detection of proteinuria. Diabetes, hypertension, and gout for 5 to 10 years should be tested at least once every half to 1 year. Take care to avoid drugs that may cause kidney damage: such as antipyretic and analgesics, some antibiotics and unknown Chinese medicine. If necessary, use under the guidance of a doctor.