**1. Introduction**

Renal biopsy is an invasive specialized test aimed at obtaining renal tissue for histologic diagnosis of a variety of kidney diseases. Kidney biopsy is generally indicated when, (1) the cause of kidney disease cannot be sufficiently determined or predicted clinically or by less invasive diagnostic procedures, (2) clinical features suggest parenchymal disease that can be diagnosed by pathologic evaluation and (3) the differential diagnosis includes diseases that have different treatments, prognosis or both [1].

Common indications for renal biopsy in practice include adult nephrotic syndrome, steroid resistant or clinically atypical nephrotic syndrome in children, glomerulonephritis, acute kidney injury (AKI) of unknown aetiology, systemic diseases with renal involvement, and persistent proteinuria or haematuria with reduced renal function. Sometimes diagnosis of kidney disease is clinically apparent, however a biopsy may be required for confirming diagnosis, assessing disease activity, chronicity and severity, e.g. in systemic lupus erythematosus [2].

#### *Renal Diseases*

Renal biopsy may be associated with complications such as bleeding, pain, infections, injury to contiguous structures, and very rarely loss of a kidney or death of the patient. The safety and usefulness of renal biopsy in the diagnosis, monitoring and treatment of renal parenchymal diseases largely depends upon correct selection and adequate preparation of the patient, the skillfulness of the operator, and the technique used.

Over the years there has been a continuous refinement of renal biopsy techniques. It is mostly performed percutaneously using imaging guidance and more sophisticated soft-tissue needles (**Figure 1a**-**c**) of varying sizes. Other

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*Renal Biopsy: Appraisal of the Methods DOI: http://dx.doi.org/10.5772/intechopen.86755*

tions to the percutaneous approach.

**2. Methods of renal biopsy**

patient care and outcome.

**2.1 Percutaneous blind**

to obtain adequate tissue.

**2.2 Percutaneous ultrasound guided**

non-percutaneous techniques such as transjugular renal biopsy, laparoscopic and open renal biopsy are also being performed especially in patients with contraindica-

Iversen and Brun introduced percutaneous renal biopsy (PRB) of native kidneys

in 1951, when they performed the procedure in a sitting patient using an aspiration needle after localizing the kidney with intravenous pyelography [3]. Although this innovation revolutionized the nephrology practice at the time, the tissue yield was inadequate in up 47% of the biopsies they performed over time [3]. Since then other percutaneous methods have been introduced and practiced with better tissue yields of up to 95–99% in some series [4–6]. Despite these encouraging figures, the tissue obtained is sometimes not diagnostically useful. This can be due to poor patient selection, wrong or poor technique, and inappropriate tissue handling, i.e., division of tissue for the different histopathologic examinations, and storage. The nephrologist should be adequately knowledgeable of indications, contraindications and complications of renal biopsy, and the several techniques available. This will significantly help to improve the usefulness of this procedure in terms of individual

Renal biopsy may be performed by one of the following approaches: percutaneous blind, blind after localisation with ultrasound scan, percutaneous real-time ultrasound guided, percutaneous CT guided, transjugular renal biopsy, laparoscopic renal biopsy, and open renal biopsy. The choice of technique among physicians often depends on skillfulness, availability of equipment and compelling

This technique is now obsolete in advanced countries, but still being practiced in some centres in low and low-middle income countries. The patient is placed in the prone position with a pillow or towel under the abdomen; the lower pole of the kidney to be biopsied is localised using the anatomic landmark (the tip of the twelfth rib posteriorly). Thereafter the skin is prepped, draped, and local anaesthetic is used to infiltrate the skin down to the kidneys. Either the manual (Tru-Cut) or spring-loaded biopsy needle is inserted through a nick made on the anaesthetized skin, and advanced towards the renal capsule while patient breaths gently. When the needle just pierces the renal capsule (signified by a give and swinging of the biopsy needle with respiratory excursions), the patient is instructed to hold the breath, and the biopsy cut is taken. Patient is observed usually for at least 6–8 hours, but may require longer admission depending on the presence of complications. This technique can be cumbersome and potentially associated with complications; tissue yield is often not optimal and several passes may be required

Percutaneous ultrasound guided biopsy is the standard of care [7]. This technique can be performed blind after localizing the kidney with an ultrasound probe, or performed with real-time ultrasound guidance. The patient is placed in a prone position with a towel or pillow beneath the abdomen to ensure proper positioning and to stabilize the kidney. The lower pole of the

indications in the patient. The techniques are briefly described below.

non-percutaneous techniques such as transjugular renal biopsy, laparoscopic and open renal biopsy are also being performed especially in patients with contraindications to the percutaneous approach.
