What is IgA Nephropathy?

IgA Nephropathy (also known as Berger's disease, IgA nephritis or synpharyngitic glomerulonephritis) is the most common form of glomerulonephritis worldwide and can result in end-stage renal disease .1 In cases of IgA Nephropathy, a galactose-deficient IgA1 isoform enters the circulating blood where it is detected by the immune system. As a result, pathogenic immune complexes are formed that accumulate in the glomeruli of the kidneys. This accumulation of immune complexes causes kidney inflammation and increased production of extracellular matrix components, leading to lesions and destruction of the renal filtering units (glomeruli). As the loss of glomeruli increases, there is a corresponding decrease in the glomerular filtration rate (GFR), the main parameter used to assess renal function.2 


As a rule, IgA Nephropathy progression occurs very slowly over time, but the chronological course of the disease can differ greatly from individual to individual. 25-30% of patients develop end-stage renal disease within 20-25 years.3 For this reason, it is essential that the disease is diagnosed at the earliest stage possible and those individuals with a high risk of progression are identified. In this way appropriate treatment can be initiated to slow the progression to chronic renal failure as much as possible.4

The various forms of manifestation and symptoms of Berger’s disease

IgA Nephropathy can be manifested in a wide range of symptoms; it can take the form of an asymptomatic disease with normal urine signs and intact renal function while in extreme cases there is rapid deterioration to end-stage renal disease.1,5


But how is IgA Nephropathy diagnosed? The main challenge when it comes to diagnosis is that IgA Nephropathy is generally asymptomatic in its early stages so that it can remain undetected for many years. In addition, the initial signs of IgA Nephropathy tend to be nonspecific symptoms, such as urine which contains blood (haematuria), or is dark-coloured and/or frothy (proteinuria) and the disease is usually first diagnosed simply by chance during a routine examination. Symptoms like blood in the urine also often occur in association with disorders of the upper respiratory tract (in some 10-15% of cases6), and this, of course, rapidly causes alarm among those affected. Subsequent differential clinical examination then frequently leads to the diagnosis of IgA Nephropathy.5 To date, no specific biomarkers for IgA Nephropathy have been identified, so that a kidney biopsy is necessary to confirm any tentative diagnosis.1


A doctor measuring a IgAN-patient's blood pressure]

The most common symptoms of IgA Nephropathy1

  • Micro- or macrohaematuria (invisible or visible blood in the urine)

  • Proteinuria (frothy and/or dark-coloured urine)

  • Hypertension

Learn more about IgAN

Who can be affected?

Who can be affected?

How much do you know about the ethnic, geographical, age-related and gender-specific differences in terms of the incidence of IgA Nephropathy? Learn more about the individuals who are affected by this disease.

Clinical course

Clinical course

Obtain an overview of the stages of IgA Nephropathy and how the disease is manifested. Click here to learn more about the characteristic progression of the disease and those factors that can exacerbate it.

Causes of IgA Nephropathy

Causes of IgA Nephropathy

Learn about the pathogenesis of IgA Nephropathy : Learn how IgAN has its origin in the gut, the role played by the peyer’s patches and IgA in the development of the disease and what causative factors there are. 


  1. Seikrit C et al. Precision medicine in immunoglobulin A Nephropathy: still a journey ahead. Nephrol Dial Transplant 2021; 36(Suppl 2): 24–30. 
  2. Boyd JK et al. An update on the pathogenesis and treatment of IgA Nephropathy. Kidney Int 2012; 81(9): 833–843. 
  3. Kidney Disease: Improving Global Outcomes (KDIGO) Glomerular Diseases Work Group. KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Kidney Int 2021; 100(4S): 1–276.
  4. Shlipak et al. The case for early identification and intervention of chronic kidney disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference. Kidney Int 2021; 99(1): 34–47. 
  5. Rodrigues JC, Haas M, Reich HN. IgA Nephropathy. Clin J Am Soc Nephrol 2017; 12(4): 677–686. 
  6. Ibels LS, Györy AZ. IgA Nephropathy: Analysis of the natural history, important factors in the progression of renal disease, and a review of the literature. Medicine (Baltimore) 1994; 73(2): 79–102.