INTERVENTIONAL ULTRASOUND: RENAL BIOPSY.

The study of renal biopsy by light microscopy, immunofluorescence and electron microscopy allowscorrect diagnosis andtherapy of acute and chronic renal diseases. The most important indications in clinical practice are numerous, as elevated serum creatinine, hematuria, nephritic or nephrotic syndrome and systemic diseases with renal dysfunction. The absolute contraindications are generally represented by uncontrolled bleeding diathesis, severe arterial hypertension, multiple renal cysts, renal mass, acute pyelonephritis, end-stage kidney disease with small kidneys. In the classic procedure of percutaneous renal biopsy the patient is in prone position, while in patients obese or with respiratory problems has been successfully used the supine anterolateral position. The technique has significantly improved by the introduction of automated-gun biopsy devices and real-time ultrasound guidance which allows visualization of the biopsy needle and its path during the procedure. The bleeding complications include silent hematoma detected only by post-biopsy imaging, macroscopic hematuria, large hematoma and blood loss requiring erythrocyte transfusion, arteriovenous fistula, pagekidney and, rarely, the need for emergent angiographic intervention or nephrectomy. The main finding of the literature is that a renal biopsy should be regarded as a safe and successful procedure, and the overall rate of major complications is very low if general contraindications are respected. The declining trend in the performance of renal biopsy by practicing nephrologists should be alarming, while the importance should be emphasized because the information provided by this procedure directly affects the care of nephropathic patients.