What is IgA nephropathy

TL;DR: IgA nephropathy (also known as Berger’s disease) is a chronic autoimmune kidney disorder that occurs when an antibody called immunoglobulin A (IgA) builds up in the kidneys, causing inflammation and damaging the filters that clean your blood. While it is a leading cause of kidney failure globally, the disease progression varies significantly between individuals, with many people maintaining stable kidney function for decades.

What exactly happens in IgA nephropathy?

IgA nephropathy affects the glomeruli, which are the tiny, delicate structures in your kidneys that filter waste and excess fluid from your blood. In a healthy body, IgA is an antibody that helps fight off infections. In individuals with IgA nephropathy, abnormal IgA molecules clump together and deposit within the glomeruli. This accumulation triggers an inflammatory response, which can lead to scarring (glomerulosclerosis) and impair the kidney’s ability to function properly. Over time, this damage can lead to the leakage of protein or blood into the urine, and in some cases, a gradual decline in overall kidney function.

How common is IgA nephropathy and who does it affect?

IgA nephropathy is considered the most common form of primary glomerulonephritis worldwide. While it can affect anyone, it is most frequently diagnosed in young adults, typically between the ages of 15 and 35. Research indicates that it occurs more often in men than in women, with a ratio of approximately 2:1. Geographically, there is a notable variation in prevalence, with higher rates observed in East Asian populations compared to those of European or African descent. Currently, 347 members of the DiseaseMaps.org community are living with this condition, sharing their unique experiences and management strategies.

What are the key clinical features of IgA nephropathy?

Because IgA nephropathy often progresses slowly, many people may not experience symptoms in the early stages. When symptoms do appear, they can be subtle or sudden. Key clinical identifiers include:

• Hematuria: Blood in the urine, which may be visible (making urine look tea-colored or cola-colored) or only detectable under a microscope.


• Proteinuria: Excess protein in the urine, often appearing as foamy or bubbly urine.


• Hypertension: High blood pressure, which is both a common symptom and a factor that can accelerate kidney damage.


• Edema: Swelling, most commonly noticed in the hands, feet, or around the eyes due to fluid retention.


• Flank pain: Discomfort in the side or back, though this is less common.

How is IgA nephropathy distinct from other kidney diseases?

Unlike some other forms of kidney disease that are caused by systemic autoimmune conditions like lupus or diabetes, IgA nephropathy is a "primary" glomerular disease, meaning the pathology is localized to the kidneys. A definitive diagnosis is typically made through a kidney biopsy, which allows pathologists to visualize the characteristic IgA deposits. Clinicians often use the MEST-C scoring system to classify the severity of the tissue damage, which helps in determining the most appropriate treatment plan for each patient.

Next steps

• Consult a nephrologist: If you suspect you have kidney issues, seek a referral to a specialist who has experience in managing glomerulonephritis.


• Monitor blood pressure: Strict blood pressure control is the cornerstone of managing IgA nephropathy and preserving kidney function.


• Join the community: Connect with the 347 members on DiseaseMaps.org to share experiences and learn from others navigating life with this diagnosis.


• Stay informed: Keep a record of your urine protein levels and blood creatinine/eGFR results to discuss with your care team.

Medical disclaimer: This information is for educational purposes only and does not constitute professional medical advice, diagnosis, or treatment; always seek the guidance of your physician or qualified health provider with any questions regarding a medical condition.

References

• NIH GARD: IgA Nephropathy Overview


• Orphanet: Rare Disease Database (Search: IgA Nephropathy)


• Kidney Disease: Improving Global Outcomes (KDIGO): Clinical Practice Guidelines for Glomerular Diseases


• OMIM: IgA Nephropathy (Entry 161950)