Free-hand ultrasound-guided renal biopsy: report of 650 consecutive cases.

In the past 4 years we have carried out 650 percutaneous renal biopsies (PRB), 54 on transplanted and 596 on native kidneys. PRB was performed with a 14-gauge one-piece disposable needle that was introduced free-handedly into the lumbar wall without any form of fixed guidance or support. Ultrasound was used to locate the kidney pole and to follow the progression of the needle tip in the renal parenchyma. The time needed for the whole procedure was about 5 min. The tissue specimen was adequate for histological evaluation in 98.8% of the cases. The prevalence of post-biopsy complications (haematuria, pain, anaemia) was 2.5%. Haematuria was not a common complication (1.6%) in our series, whereas clinically silent perirenal haematoma was common. Mild perirenal bleeding (volume < 5 ml) was found in 40 of a series of 150 patients (26.6%) who underwent ultrasound scan 24 h after the PRB. Haematoma exceeding 100 ml was revealed with US in only 0.6% of the patients. We conclude that free-hand ultrasound-guided PRB makes this technique easier, highly successful, time-saving and almost free of severe side effects.