Kidney biopsy (PG043)

Kidney biopsy — is a procedure for obtaining a small fragment of kidney tissue (parenchyma) for pathological examination. It is most often performed by percutaneous puncture under ultrasound or CT guidance. The study with the code PG043 is a key method for diagnosing complex kidney diseases that cannot be accurately determined using urine tests or imaging methods.

Research objective: The main task is to establish an accurate diagnosis in systemic diseases, nephrotic syndrome or suspected tumor. Biopsy allows to assess the degree of damage to the structural units of the kidney - nephrons, vessels and interstitial tissue, which is critically important for the selection of aggressive therapy (for example, hormonal or immunosuppressive).

What does the pathologist evaluate:

• Glomeruli condition: looking for signs of glomerulonephritis, sclerosis, or immune complex deposits.

• Tubular apparatus: detection of signs of dystrophy, necrosis or atrophy of the tubular epithelium.

• Interstitial tissue: assessment of the severity of edema, inflammatory infiltration, or fibrosis (replacement of functional tissue with connective tissue).

• Vascular bed: detection of signs of vasculitis, arteriosclerosis or diabetic angiopathy.

• The nature of the neoplasms: Differentiation of benign tumors (e.g., angiomyolipomas) from renal cell carcinoma.

Clinical significance: For a nephrologist, the results of a kidney biopsy are crucial in determining the prognosis of the disease. The study helps to understand whether the process is reversible against the background of treatment, or whether the disease has already entered the stage of irreversible fibrosis (nephrosclerosis). This allows you to avoid prescribing potentially toxic drugs if they are no longer effective, or, conversely, to start therapy in time to preserve kidney function.

When is it prescribed:

• persistent presence of protein in the urine (proteinuria) or blood (hematuria) of unknown origin;

• rapid decline in kidney function (increased creatinine levels);

• suspected systemic diseases with kidney damage (systemic lupus erythematosus, vasculitis, amyloidosis);

• the need to monitor the condition of the transplanted kidney;

• verification of focal renal lesions before planning surgery.