When kidneys do not work well, proteins leak through kidney filters and reach urine, resulting in protein excretion. This article elucidates the causes behind asymptomatic proteinuria.
Proteins are large molecules that are responsible for several activities in the body. Proteins are made of thousands of small units called amino acids. The sequential arrangement of amino acids determines the structure and functions of each protein. Proteins help in building strong bones and muscles. Proteins also prevent infections and control the entry of excess fluids into the blood.
Proteinuria is an abnormal condition where the kidney releases abnormal levels of protein in the urine. This condition often occurs as a sign of kidney disease. Usually, kidneys do not allow proteins to flow into the urine. When a kidney gets diseased, proteins like albumin might leak into the pee. A person may have proteinuria even when the body makes excess proteins. Kidney diseases do not show any early symptoms. But protein in urine occurs as the initial sign.
Asymptomatic proteinuria occurs due to diseases affecting the glomeruli. These glomeruli are clusters of small blood vessels having tiny pores in the kidney through which blood is filtered.
There is a steady or intermittent loss of small quantities of protein in the urine in this condition.
These small amounts of protein in urine are discovered in people without any symptoms where urine tests are done for some other purpose.
Asymptomatic proteinuria can also occur in a person recovering from kidney inflammation (nephritis). If nephritis remains the cause, the doctor needs to check the patient for the next few weeks or months to ensure that the abnormality has resolved.
If proteinuria persists without any symptoms, the cause behind them will be the following disorders.
Immunoglobulin (IgA) nephropathy is otherwise known as Berger’s disease. This condition occurs when damage to the tiny filters inside the kidney occurs. IgA is a protein that helps in fighting against infections attacking the body. In people affected with IgA nephropathy, these proteins accumulate and form clumps inside the glomeruli. Thus glomeruli get damaged due to these proteins. This damage causes chronic kidney disease, and in severe cases, it results in chronic kidney failure or end-stage renal disease (ESRD).
Symptoms of IgA Nephropathy:
There are no specific symptoms noticed in the early stages of IgA nephropathy. A person can survive without any symptoms for years. The initial sign appears when a person gets an infection. The affected person may notice his urine pink or brown, indicating blood in the urine. Some patients may have protein in the urine. When a person has protein in the urine, the urine appears foamy with hand or feet swelling.
A routine urine test helps in diagnosing this condition. When the usual urine test shows blood or protein in the urine, the doctor advises the patient to do blood tests to check the kidney health.
When blood and urine tests show signs of kidney damage, the doctor proceeds to do a kidney biopsy. In this procedure, a needle is inserted into the kidney to remove a piece of kidney tissue. The doctor looks at the sample under a microscope to diagnose the cause.
Complications of IgA Nephropathy:
The common complications observed in patients affected with IgA nephropathy are high blood pressure and high cholesterol. Elevated levels of cholesterol increase the risk of developing heart problems in a person.
Treatment of IgA Nephropathy:
A person with IgA nephropathy needs regular testing to monitor his kidney health. The doctor suggests ACE (angiotensin-converting enzyme) inhibitor or ARB (angiotensin II receptor blockers) to control blood pressure and prevent protein loss in urine. The affected person may also be advised to change his diet and some medications to control cholesterol. In some cases, immunosuppressants are recommended.
Alport syndrome is a genetic disease caused by a defective gene in the X chromosome. Alport syndrome can cause chronic kidney disease, and in some cases, kidney failure occurs.
Symptoms of Alport Syndrome:
Females having a defective gene in one of their two X chromosomes do not develop any symptoms. But their kidneys function less efficiently.
Males having a defective gene in one X chromosome develop severe problems because males do not have a second X chromosome to compensate for their defect. Alport syndrome can also affect other organs. Hearing problems and cataracts can also occur. Abnormalities occurring on the cornea or retina can result in blindness.
This condition is diagnosed by doing urinalysis, kidney biopsy, and molecular genetic analysis. These diagnostic tests are often suggested in people having blood in urine and a family history of chronic kidney disease.
There is no specific therapy for this condition. People developing kidney failure need dialysis or a kidney transplant.
Thin basement membrane syndrome (TBMD) is an inherited disorder affecting the glomeruli of kidneys.
The main symptom observed is blood in urine and protein in the urine. There are no other specific symptoms observed in most cases, and in some cases, high blood pressure and body swelling are observed.
The doctor does urine and blood tests to see the working condition of the kidney. The urine test checks the amount of protein, blood, and other parameters that indicate kidney damage. A blood test for serum creatinine calculates the glomerular filtration rate. This parameter shows the rate of waste filtered by the kidneys from the blood. A kidney biopsy helps to confirm the diagnosis. This disorder produces unique changes in the blood vessels of the glomeruli, which can be detected by electron microscopy.
In most cases, TBMD occurs as a benign condition where the long-term prognosis of the affected person is good. In some cases, complications arise, and further treatment is required.
Currently, there is no specific treatment for TBMD. Medications taken for high blood pressure and chronic kidney disease are prescribed. To reduce any swelling, the doctor may prescribe diuretics. In rare cases, dialysis or kidney transplant is done when kidney failure occurs.
When protein levels remain high without causing any symptoms, make sure to consult a doctor to find the exact cause and take treatment accordingly.
Last reviewed at:
29 Dec 2021 - 4 min read
Most Popular Articles
Do you have a question on Asymptomatic Proteinuria or ?Ask a Doctor Online