Objective: Percutaneous renal biopsy is an essential tool in the diagnosis of patients with renal parenchymal diseases. Although the methods have improved after the launch of real-time ultrasonic guidance, renal biopsy is still not a risk-free procedure. Thus, an improvement of the method is necessary.

Methods: We describe our experience with intrabiopsy color ultrasound guidance in 23 consecutive percutaneous native kidney biopsies. The results of the patients who underwent them, studied prospectively, are compared to these of 28 other patients who underwent ultrasound guided percutaneous native kidney biopsies with grayscale ultrasound guidance - studied retrospectively. The patients ranged in age from 20 to 78 yrs, with a mean age of the group with color ultrasound guidance of 46 yrs. and of the group with grayscale ultrasound guidance – 44 yrs. Before biopsy all patients were evaluated and found to have normal coagulation system. One specimen of tissue was obtained from each patient.

Results: Of the 23 patients studied prospectively, clinically significant complications developed in only one. He had perirenal hematoma. In the group without color ultrasound guidance complications appeared in 5 patients (17.9%), including gross macroscopic hematuna which cleared within 12 hours of observation in one of the patients and perinephric hematoma with varying sizes in four of them. Diagnostically satisfactory material containing an average of 9 glomeruli per specimen was obtained from prospectively studied group and 8 glomeruli from retrospectively studied group.

Conclusions: Color sonography could be considered as a suitable method decreasing the risks of postbiopsy complications.