Should You Consider a Kidney Biopsy for Unexplained Proteinuria?

Should a kidney biopsy be performed?

Hello, doctor.
I am the patient who previously inquired about "unexplained proteinuria" (I have had persistent protein in my urine for 3-4 years and am currently managing it with Aprovel and Persantin).
In the past year of follow-up visits, my protein levels have improved, fluctuating between "normal and +1." The doctor mentioned that it does not seem severe enough to warrant a kidney biopsy (leaving the decision to me).
However, taking medication has been disruptive to my life, and I am hesitant to stop the medication without a clear treatment plan.
Given my situation, would you recommend a biopsy to identify the underlying cause? Would finding the cause increase the chances of effective treatment? I have many questions and would appreciate your guidance.
Thank you!

Lin Sir, 30~39 year old female. Ask Date: 2017/01/12

Dr. Wu Hongjie reply Internal Medicine

The following are common reasons for performing a kidney biopsy:
At onset:
1.
Clinical pure proteinuria > 3 grams/day, along with suspicion of other possible lesions within the kidneys.
2.
Nephrotic syndrome in non-pediatric patients (urinary protein > 3 grams/day).
Intermediate:
Persistent proteinuria, and ineffective response to corticosteroids or medications aimed at reducing proteinuria (ineffective response is defined as remaining > 0.3 grams/day after treatment).
Later:
1.
Recurrent nephritic syndrome.
2.
Nephritis unresponsive to corticosteroids.
3.
Clinical progression that differs from the expected disease course.
4.
Rapidly progressive renal function deterioration.
5.
Chronic kidney disease with preserved kidney size.
Based on your situation, if the treatment has effectively reduced urinary protein to < 0.3 grams/day, a biopsy may help identify the underlying cause, but it may not significantly impact the outcome.
Even if a cause is identified, chronic conditions lasting more than three months that have not improved are typically difficult to treat, and management will primarily involve medication control.

Reply Date: 2017/01/12

More Info

When considering whether to undergo a kidney biopsy for unexplained proteinuria, it is essential to weigh the potential benefits against the risks and to understand the context of your specific situation. Proteinuria, or the presence of excess protein in the urine, can be a sign of kidney damage or disease. In your case, you have been experiencing proteinuria for several years, and your recent tests show fluctuations in protein levels, which can be concerning.

A kidney biopsy is a procedure that allows doctors to obtain a small sample of kidney tissue for examination under a microscope. This can help identify the underlying cause of kidney problems, including various forms of glomerulonephritis, diabetic nephropathy, or other kidney diseases. However, it is generally recommended only when there is a strong suspicion of significant kidney disease that could be treated differently based on the biopsy results.

According to current medical guidelines, a kidney biopsy is typically not performed in patients with low-grade proteinuria (less than 500 mg/day) unless there are other concerning symptoms or laboratory findings. In your case, with protein levels fluctuating between normal and +1, it may not meet the threshold for a biopsy. The decision to proceed with a biopsy should be made collaboratively with your nephrologist, who can assess your overall clinical picture, including your blood pressure, kidney function, and any other symptoms you may have.

If your nephrologist believes that the proteinuria is not indicative of a severe underlying condition and that your kidney function remains stable, they may suggest continuing your current management plan, which includes medications like Aprovel (an antihypertensive) and Persantin (an antiplatelet agent). These medications can help manage blood pressure and reduce the risk of kidney damage, which is crucial in patients with proteinuria.

However, if you are experiencing significant side effects from your medications or if your quality of life is being affected, it is essential to communicate this with your doctor. They may consider adjusting your treatment plan or exploring alternative therapies that could be less burdensome.

In terms of lifestyle modifications, maintaining a healthy diet, controlling blood pressure, and managing any underlying conditions (such as diabetes) are critical steps in protecting your kidney health. A low-sodium diet and limiting protein intake may also be beneficial, particularly if you have any signs of kidney dysfunction.

Ultimately, the decision to undergo a kidney biopsy should be based on a thorough discussion with your healthcare provider, considering your specific circumstances, the potential risks and benefits of the procedure, and your overall health goals. If you feel uncertain or uncomfortable with your current nephrologist's recommendations, seeking a second opinion from another kidney specialist may provide additional insights and help you make a more informed decision regarding your care.

Similar Q&A

Should You Consider a Kidney Biopsy for Unexplained Proteinuria?

Dr. Wu Hongjie reply Internal Medicine
The following are common reasons for performing a kidney biopsy: At onset: 1. Clinical pure proteinuria > 3 grams/day, along with suspicion of other possible lesions within the kidneys. 2. Nephrotic syndrome occurring outside of childhood (proteinuria > 3 grams/day). Inte...

Should You Consider a Kidney Biopsy for Unexplained Renal Dysfunction?

Hello Dr. Chen, I have been experiencing renal insufficiency for about 4 years now. I have undergone an ultrasound examination, and the kidney size was normal. Currently, I am undergoing regular follow-up checks. My creatinine levels are around 1.7, and my blood urea nitrogen is ...

Dr. Chen Qiunan reply Urology
Hello Pan, based on the information you provided, there are no obvious signs of glomerulonephritis. Generally, kidney diseases can be classified as primary or secondary. Primary kidney diseases mostly refer to primary glomerulonephritis. If there is proteinuria or hematuria, trea...

Understanding Proteinuria: Should You See a Nephrologist?

Hello Doctor, during this year's employee health check, I found (+) urine protein and (+/-) occult blood. I have had similar test results in the past, but after several rechecks, they disappeared. However, I occasionally test positive again, and sometimes my white blood cell...

Dr. Yang Jun reply Internal Medicine
Hello: In response to your question, the presence of proteinuria can be classified into functional proteinuria and pathological proteinuria. Functional proteinuria may occur due to urinary tract infections, fever, infections, or during a woman's menstrual period, and it typi...

Understanding Proteinuria: Health Implications and Specialist Consultation

During a health check-up, I found out that I have protein in my urine, and I am not familiar with "proteinuria." I am unsure of its impact on my health. If I need to seek medical attention, which specialty should I consult?

Dr. Li Junde reply Surgery
Miss Ah-Hui: Your question is answered as follows: Proteinuria is one of the items in a routine urinalysis, which can be assessed qualitatively and quantitatively. Generally, it indicates the amount of protein present in the urine, which should be absent or only in trace amounts ...