What Is IgA Nephropathy (IgAN)?

Immunoglobin A nephropathy (also known as IgAN or Berger's disease) is a rare kidney disease that occurs when your immune system mistakenly attacks the kidneys and produces excess IgA (a type of antibody). This affects your kidneys' ability to properly filter waste from your blood, causing symptoms like changes in urine color, swelling, fatigue, and a higher risk of infections.

Researchers are unsure about the exact cause of IgAN, though risk factors like a family history of the condition can increase your odds of developing it. Without proper treatment, IgAN can lead to kidney failure, so it's essential to seek care from your healthcare provider early on and get the support you need to prevent complications.

IgA Nephropathy Symptoms 

IgA nephropathy doesn’t cause symptoms right away. People with this condition can live years or decades without any signs. However, when symptoms do develop, you may experience:

• Changes in urine color, often due to blood in your pee
• Foamy or cloudy urine
• Sore throat
• Frequent respiratory infections
• Swelling in the legs, ankles, and feet
  
• Hypertension (high blood pressure)
• Abdominal pain
• Back pain
• Fatigue
• Muscle weakness
  

Causes

IgA nephropathy is an autoimmune disorder that occurs when the immune system mistakenly attacks the kidneys. When this happens, your body starts to produce more IgA, an antibody that plays a role in your overall immune function.

Researchers believe people with this condition produce more IgA that is low in the sugar galactose. The immune system recognizes this abnormal IgA as a foreign invader, leading to the production of autoantibodies. As a result, this can trigger an immune response when the antibodies collect in the kidneys.

As a result of this reaction, IgA builds up in the kidneys, damaging the blood vessels (known as glomeruli) that help filter your blood and remove toxins and waste. This leads to inflammation and damage, making it difficult for your kidneys to function properly. While the exact cause of this response is unknown, researchers believe that a combination of genetic and environmental factors can trigger the onset of this condition.

 Risk Factors

Experts have identified some factors that can raise your risk of IgAN. These include:

• Family history of IgA nephropathy or IgA vasculitis (a condition that causes swelling and redness throughout the body)
• Personal history of celiac disease, hepatitis, or liver cirrhosis
• Being between the ages of 10 and 40
• Being assigned male at birth

Signs and Symptoms of IgA Nephropathy

How To Treat IgA Nephropathy (Berger's Disease)

What Causes IgA Nephropathy (Berger's Disease)?

The Stages of IgA Nephropathy (Berger's Disease)

The Diagnostic Process

One of the main goals in the diagnostic process of IgA nephropathy is to rule out other potential causes of your symptoms. Other conditions that may cause symptoms similar to IgAN include IgA vasculitis, post-streptococcal glomerulonephritis (a kidney infection), lupus, and kidney or urethral cancer.

During your appointment, you can expect your provider to ask about your medical history and perform a physical exam. However, they may also order other tests to learn more about your health status. These tests may include:

• Urinalysis: Collecting a sample of urine and examining it for signs of blood or infection
• Blood tests: Detecting abnormal levels of proteins and signs of inflammation or cellular damage
• Urine protein: Checking for elevated levels of protein in the urine
• Estimated glomerular filtration rate (eGFR): Measuring how effectively your kidneys are working by tracking how much blood they’re able to filter
• 24-hour urine test: Tracking how well your urine retains proteins
• Kidney biopsy: Removing a sample of your kidney tissue to check for signs of disease and damage

How To Determine What Stage of IgAN You're In

If you receive a diagnosis for IgAN based on your test results, your provider will also determine what stage of the condition you're in. Healthcare providers use the MEST-C system to stage your condition, which measures the following factors: 

• Mesangial cellularity (M): Checks for increased numbers of mesangial cells in the glomerulus (the filter of the kidney)
• Endocapillary hypocellularity (E): Measures extra cells inside the capillaries of the glomerulus
• Segmental glomerulosclerosis (S): Assesses whether blood vessels in the glomerulus are scarring or sticking together
• Tubular atrophy (T): Evaluates the amount of decay (atrophy) or scar tissue (fibrosis)
• Cellular crescents (C): Analyzes if cellular crescents (extra layers of cells) have formed outside of the glomerulus

IgA Nephropathy Treatment

While there is no cure for IgA nephropathy currently, several treatments can slow the progression of the disease and prevent kidney damage. Additionally, more treatments are being studied as research in IgAN increases. Your exact treatment plan will depend on the severity of your condition and the stage of IgAN you're in, but may include lifestyle changes, medications, and surgery.

Lifestyle Changes

Since high blood pressure can occur as a result of IgAN, your healthcare provider may recommend certain lifestyle changes to manage the condition. They may recommend:

• Eating a low-sodium diet
• Avoiding or quitting smoking
• Managing weight if you live with obesity
• Increasing your physical activity levels
  

Prescription Medications

Medications for IgAN help reduce high cholesterol, regulate blood pressure and blood protein, remove excess fluid, and influence immune function to manage symptoms and prevent kidney damage. Your provider may prescribe:

• Angiotensin receptor blockers (ARBs) like Edarbi (azilsartan), Atacand (candesartan), and others
• Angiotensin-converting enzyme (ACE) inhibitors including Lotensin (benazepril) and Zestril (lisinopril)
• Statins such as Lipitor (atorvastatin) and Crestor (rosuvastatin)
• Corticosteroids like Delatson (prednisone), Entocort (budesonide), or Medrol (methylprednisolone)
• Diuretics (water pills)

Surgery

Some cases of IgA nephropathy may benefit from a tonsillectomy, a surgery that removes your tonsils in the throat. This treatment is well-tolerated, but more research is needed to confirm its effectiveness as data is currently mixed. For this reason, it's not usually the first line of treatment for cases in the United States.

In certain cases, IgA nephropathy can get very severe, which can lead to kidney failure. If you're experiencing late-stage IgAN, you may need kidney transplant surgery or dialysis, which uses a machine to filter blood for your kidneys.

How To Prevent Kidney Damage

Because IgAN is an autoimmune disorder, there aren't any surefire ways to prevent the condition from developing. However, there are some things you can do to lower the risk of kidney failure and prevent further kidney damage. These prevention strategies include:

• Reducing your sodium intake
• Eating heart-healthy foods such as whole grains, fruits, vegetables, and lean meats
• Increasing your physical activity
• Getting at least seven hours of sleep per night
• Avoiding or quitting smoking
• Limiting your alcohol intake
• Managing underlying conditions like high blood pressure, high cholesterol, and diabetes
  

Related Conditions

Though IgA nephropathy typically progresses very slowly, it can worsen and increase the risk of other health conditions that affect your kidneys and overall health. Without treatment, you may have a higher risk of developing the following:

• Chronic kidney disease: Over time, the damage due to IgAN causes chronic kidney disease, in which the kidneys become damaged and less able to function.
• Kidney failure: Chronic kidney disease triggered by IgAN can eventually lead to end-stage renal disease and kidney failure. This happens in about 30% of adults who have had IgA nephropathy for 20 or more years.
• Heart failure: End-stage renal disease due to IgAN also affects cardiovascular health, increasing the risk of heart failure, which causes the heart muscles to be unable to pump enough blood.

Living With IgA Nephropathy

In terms of overall prognosis, individual cases of IgA nephropathy vary. This condition usually progresses slowly. However, you will often need persistent treatment to keep symptoms at bay and prevent complications.

Living with a chronic illness can be scary, and IgAN can affect your quality of life. However, current treatments can effectively reduce symptoms, slow down disease progression, and lower the risk of serious complications. In fact, with current treatments, several cases of IgAN end up in remission, where people no longer experience symptoms. More treatments are also on the way to help improve life expectancy and overall kidney health.