Clinical Use of the Percutaneous Renal Biopsy

Abstract
The renal biopsy is undoubtedly a justifiable diagnostic tool though it has not yet reached full maturity in clinical practice. Risks. For most patients the risks do not appear to be excessive. An added caution must be exercised in malignant hypertension but even here after careful appraisal of this added risk the biopsy may still be justified. The experience of the operator would appear to modify some of the risk. Returns. The biopsy has often added to the confusion surrounding a given case because it may be uninterpretable or because it provides an unfamiliar complex of findings. Thisresult is becoming less common with increasing experience. Even when the histology of the kidney is not diagnostic, it may suggest something of clinical value about the nature of the disease process, such as the presence of vascular disease, focal nephritis, or tubular disease of unidentified nature. The use of the electron microscope has extended the range of the percutaneous biopsy considerably. It is unfortunate that the cost and complexity of this instrument have confined it to certain centers. It should be remembered also that a number of technical failures will occur, and the sampling error may be large. Despite these real problems, the percutaneous renal biopsy is often the only way of establishing a diagnosis and makes its greatest contribution in the appraisal of the asymptomatic patient with proteinuria and an abnormal urinary sediment.