How is IgA nephropathy diagnosed?

Diagnosis of IgA Nephropathy

IgA nephropathy, also known as Berger's disease, is a kidney disorder characterized by the accumulation of immunoglobulin A (IgA) in the glomeruli, which are the tiny blood vessels in the kidneys responsible for filtering waste and excess fluid from the blood. The diagnosis of IgA nephropathy involves a combination of clinical evaluation, laboratory tests, imaging studies, and kidney biopsy.

Clinical Evaluation

The initial step in diagnosing IgA nephropathy involves a thorough clinical evaluation. The healthcare provider will review the patient's medical history, including any symptoms or risk factors. Common symptoms of IgA nephropathy include blood in the urine (hematuria), recurrent episodes of visible or microscopic hematuria, and occasionally, proteinuria (presence of excess protein in the urine). The healthcare provider will also perform a physical examination to assess for signs of kidney damage, such as high blood pressure or swelling in the legs.

Laboratory Tests

Several laboratory tests are used to aid in the diagnosis of IgA nephropathy:

• Urinalysis: A urine sample is analyzed to detect the presence of red blood cells (RBCs) and protein. Microscopic hematuria, where RBCs are visible under a microscope, is a hallmark of IgA nephropathy.


• Blood tests: Blood samples are taken to assess kidney function, measure levels of creatinine and blood urea nitrogen (BUN), and evaluate the overall health of the patient. Elevated levels of these markers may indicate impaired kidney function.


• Immunological tests: Specific immunological tests, such as serum IgA levels and IgA immune complexes, may be performed to detect abnormalities in the immune system and confirm the presence of IgA deposits in the kidneys.

Imaging Studies

Imaging studies are often conducted to evaluate the structure and function of the kidneys:

• Ultrasound: An ultrasound scan uses sound waves to create images of the kidneys. It helps identify any structural abnormalities or obstructions that may contribute to kidney damage.


• Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) scan: These imaging techniques provide detailed images of the kidneys and surrounding structures. They may be used to assess the size, shape, and condition of the kidneys.

Kidney Biopsy

A kidney biopsy is the definitive diagnostic test for IgA nephropathy. It involves the removal of a small piece of kidney tissue for microscopic examination. The procedure is typically performed under local anesthesia using a needle inserted through the skin and into the kidney. The biopsy sample is then analyzed by a pathologist to confirm the presence of IgA deposits in the glomeruli and assess the severity of kidney damage.

Additional Considerations

It is important to note that the diagnosis of IgA nephropathy requires the exclusion of other potential causes of kidney disease, such as systemic lupus erythematosus, vasculitis, and other glomerular diseases. This is done through a comprehensive evaluation of the patient's clinical presentation, laboratory results, and imaging findings.

In conclusion, the diagnosis of IgA nephropathy involves a combination of clinical evaluation, laboratory tests, imaging studies, and kidney biopsy. Clinical evaluation includes reviewing the patient's medical history and performing a physical examination. Laboratory tests, such as urinalysis and blood tests, help assess kidney function and detect abnormalities in the immune system. Imaging studies, such as ultrasound, MRI, or CT scans, provide detailed images of the kidneys. However, the definitive diagnosis is made through a kidney biopsy, where a small sample of kidney tissue is examined under a microscope to confirm the presence of IgA deposits. It is crucial to exclude other potential causes of kidney disease during the diagnostic process.