Proteins play an important role in your body such as building muscles and bones, preventing infections and controlling the amount of fluid in your blood. There are two main plasma proteins in your blood: albumin and globulin. The kidney is responsible for recapturing these proteins by filtering the blood by removing wastes and getting rid of them in the form of urine. Blood flows into the kidney through the renal artery which branches into smaller blood vessels which in turn enter the nephrons.
As blood flows into the nephron, it enters a cluster of tiny blood vessels known as the glomerulus. The glomerulus has thin walls that allow the absorption of small molecules (including proteins), fluids (water) and wastes into the tubule. There runs a blood vessel next to the tubule which reabsorbs water, minerals and nutrients out of this mixture and sends it back into the blood stream through the renal vein while the waste goes into the bladder through the ureter. On the other hand, large molecules such as proteins and blood cells get retained in the blood vessel and are returned into your blood. For some reason, the filtration process may be faulty and protein levels in your blood and urine may be abnormal. What these two situations mean and the tests used to measure protein levels your blood and urine will be discussed in detail below;
PROTEIN IN YOUR BLOOD
Protein level in your blood may go high or low for various reasons. Plasma protein tests are carried out to detect the amount of proteins in your blood. The blood protein tests measure the level of albumin in your blood and compares it with that of globulin- this is known as the A/G ratio. The normal ratio is usually just above 1 (one), with albumin levels being higher. If the ration is off, it could affect the overall protein count.
Abnormal protein count in your blood could indicate various health problems. For instance, higher-than-normal protein levels indicate bone marrow disorders, infections and inflammations while low-than-normal levels potentially indicate severe malabsorption and malnutrition, kidney or liver disease and bowel problems. Low plasma protein count in pregnant women may indicate complications such as preeclampsia, low birth weight, premature birth, intrauterine growth restriction, still birth or Down syndrome. Early detection can help the doctor control the condition so that the mother can have a safe, healthy pregnancy and eventual delivery.
In case of abnormal results, the doctor may recommend a series of follow-up tests to determine the cause for the abnormal levels. Some of these tests are the C-reactive protein tests, immunoglobulin A (IgA) tests to help diagnose autoimmune diseases, liver enzyme tests and protein electrophoresis test to look for underlying bone marrow disorders.
Symptoms of abnormal protein levels
Symptoms of low protein levels include bruising easily, slow clotting of blood, fatigue, brittle or ridged nails, fatigue, hair loss, rashes, headaches and nausea.
Symptoms of high protein levels include pain in your bones, numbness or tingling in your feet, legs or hands, weight loss, excessive thirst and frequent infections.
Preparing for the Test
There are no special preparations required for the test. The doctor will need to draw some blood out of your blood vessel. The process is usually short but if you have smaller vessels, then it may take a bit longer. Some doctors may have labs in their facilities, but in most cases, one has to go to the lab to have their blood drawn. You should inform your doctor of any medications you are using as they may interfere with the test results.
Risks of plasma protein tests
There are generally few risks with protein tests. However, if you are sensitive to needles, then you should expect to feel pain and a little discomfort. You may also feel dizzy and have slight bruising at the point of puncture.
PROTEIN IN URINE
This condition is known as proteinuria or albuminuria. The normal protein elimination is less than 150 mg/day and less than 30mg of albumin/day. Temporary raised levels of protein in urine could be caused by conditions such as pregnancy, stress, strenuous exercise, diet, exposure to the cold and infections. Persistent protein in the urine can on the other hand be an early indication of a kidney disease in people with chronic medical conditions such as diabetes and/or hypertension. It can be a pointer to the possibility of one having a urinary tract infection, lupus, high blood pressure and preeclampsia in pregnant women. The latter may require additional urine test (urinalysis) to determine the reason for protein leakage.
Symptoms of protein in urine
During the initial stages of kidney damage, you may not experience any symptoms because there are only small amounts of protein in your urine. But as the condition progresses, some symptoms may begin to manifest. They include; loss of appetite, build-up of body fluid (edema) in the hands and/or feet, shortness of breath, foamy urine, nausea, frequent urination and fatigue.
Certain people are more predisposed to develop proteinuria than others. Some common risk factors include;
- Age; adults aged 65 and older are more susceptible to getting dehydrated and/or developing kidney problems. Pregnant ladies aged above 40 years also have a greater risk of preeclampsia.
- High blood pressure; Hypertension patients have higher risks for diabetes and kidney disorders.
- Diabetes; it is the most common cause of chronic kidney failure (CKD). It is also associated with glomerulonephritis and preeclampsia.
- Family History; one is more likely to develop proteinuria if they have a family history of kidney disease and preeclampsia.
- Certain ethnicities such as African Americans, Latinos, Asians and American Indians have greater risks of kidney problems.
- Being overweight or obese predisposes one to conditions such as high blood pressure, diabetes and preeclampsia.
Testing for protein in urine
The only way of finding out whether you have proteins in your urines through a urine test. The test measures the amount of albumin in your blood compared to that of creatinine. This is known as the urine albumin-to-creatinine ratio (UACR). The test involves normal urination and has ZERO risks; so, you should not be worried about discomforts. The test can either be done at home or at the lab. If it is done in the lab, you will be instructed to provide a ‘clean catch’ sample. The doctor may also request that you collect all your urine over a 24-hour period- this is done because the amount of substances in one’s urine vary throughout the day and so collecting more samples would be most preferable as it would give an accurate picture of your urine content.
The clean catch collection procedure involves the following steps;
- Wash your hands
- Clean your genital area. A male will be required to clean the tip of their penis with a clean pad while a female will be required to open their labia and clean the area in a front-to-back motion.
- Start to urinate in the toilet
- Move the collection container to your urine stream
- The collection container (specimen cup) has markings indicating amounts; so, collect at least an ounce or two of the urine.
- Finish urinating
- Return the sample container (with the urine) to your health care provider
At home, you will use a dipstick test to measure the amount of urine in your blood. A dipstick is made of a color-sensitive pad which changes color depending on the amount of protein it would detect in your blood. With this method however, its major drawback is that although small amounts of proteins are usually in the urine, it may not be detected at all. A urine microalbumin test thus falls out as being the most accurate test as it can detect any amount of protein in your urine. If your doctor thinks you have kidney issues, the test will be repeated three times in three months.
The following tests are used to determine the cause of proteinuria;
- Glomerular filtrate rate (GMR) blood test; this checks your kidney function
- Imaging Tests such as CT Scans to take a detailed photo of your kidneys and urinary tract.
- Kidney biopsy where a sample of your kidney is removed and examined for signs of kidney damage
What Could Interfere with the Results
The following may interfere with the test results;
- Medications; different medicines can change the results of the urine test. You must inform your health care provider of any medications you are currently using.
- Fluids from the vagina that get into the urine- this is why you should strictly adhere to and thoroughly follow through with the steps in getting a clean catch sample of your urine.
- Strenuous exercise
- Urinary tract infection
For a random urine sample, the normal UACR values are 0 to 14mg/dL. For a 24-hour urine collection, the normal values should be less than 80mg per 24 hours.
What abnormal results mean
Large amounts of protein in your urine, as mentioned earlier, may be due to any of the following; heart failure, loss of body fluids (dehydration), kidney problems, problems during pregnancy such as high blood pressure caused by preeclampsia, urinary tract infections or some types of cancer.
If you have temporary proteinuria, you will most likely not require any medication.
If you have persistent proteinuria, the underlying condition will need to be treated for your kidneys to resume normal functioning. Treatment may include;
- Dietary changes
- Weight loss
- Diabetes medication to control high blood glucose levels
- Blood pressure medication
Kidney plays an important role of absorbing plasma proteins. Maintaining kidney health is important to your overall health and wellbeing. Some of the ways you can do this is by incorporating a healthy diet, exercising regularly, controlling your blood sugar, quit smoking, monitor your blood pressure and drink plenty of fluids. If you have a chronic health condition, keep in mind that you are at higher risk of having issues with your protein levels- so you must work closely with your doctor to watch for signs of loss of kidney function.
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