Post renal biopsy complication rate and diagnostic yield comparing hands free (ultrasound-assisted) and ultrasound-guided biopsy techniques of renal allografts and native kidneys

Background: Real time ultrasound guided percutaneous kidney biopsy has become the standard procedure to assess the pathology of native kidneys and renal transplants. No specific technique has shown to be totally free of post biopsy bleeding complications. Few Studies have looked at the rates of post biopsy bleeding complications comparing different needle size, post biopsy haematoma size, or clinical predictors of the complication rates. In this study we aim to assess safety and adequacy of the real time ultrasound guided biopsy using free hands (ultrasoundassisted) and ultrasound-guided technique. Method: The results of 527 elective native and kidney transplant biopsy performed as a day case procedure at Lancashire Teaching Hospitals were retrospectively reviewed (499 native and 28 allograft biopsies). Biopsies were grouped into 4 groups according to the technique and the needle size; group 1 (n = 119; performed by free hands-ultrasound assistedtechnique using 14G needle) Group 2 (n = 59; performed by free hands-ultrasound-assisted technique using 16G needle), group 3 (n = 195; performed by ultrasound-guided technique using 14G), and group 4 (n = 154; performed by ultrasound-guided technique using 16G). The 4 groups were matched in age, sex, weight, haemoglobin, serum creatinine, INR, PT, and PTT time. Results: The overall tissue specimen was adequate in 80.45 % of the cases, with no difference between group 1 and 3 (81.5 and 80.52 % respectively, p = 0.82) or between group 2 and 4 (86.44 and 77.3 % respectively, p = 0.13). The overall major complications rate was 2.84 %, with no difference between group 1 and 3 (2.5 and 1 % respectively, p = 0.30) or group 2 and 4 (5 and 4.5 % respectively, p = 0.86). The overall minor complications was 3.7 % with no difference between group 2 and 4 (3.3 and 5.84 % respectively, p = 0.46), however, minor complications were higher in group 1 compared to group 3 (5.8 and 1 % respectively, p = 0.01).There was no difference between using 14G and 16G needle size in terms of tissue adequacy(p = 0.7), major complications (p = 0.2 for drop in Hb >10 g/l, p = 0.08 for blood transfusion, p = 0.35 for embolization) or minor complication items(p = 0.4 for drop in Hb, 10 g/l,p = 0.1 for haematuria, p = 0.7 for hematoma). Conclusion: When using a 14G needle, there is higher risk of minor complications in the free hands-(ultrasoundassisted) technique compared to the ultrasound-guided technique. There is no difference in the rates of major or © 2015 Ali et al. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http:// creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Open Access *Correspondence: [email protected] 1 Renal Department, Lancashire Teaching Hospitals NHS Foundation Trust, Preston, UK Full list of author information is available at the end of the article Page 2 of 6 Ali et al. SpringerPlus (2015) 4:491 Background Percutaneous needle biopsy of the kidney is one of the most important investigations in assessing renal pathology (Wiczek 1990; Gray et al. 1992; Matas et al. 1985). Technical advances in biopsy procedures have changed from a blind approach to real time ultrasound guided techniques (Donovan et al. 1991). Percutaneous renal biopsies were first performed by Iversen and Brun who used an aspiration biopsy needle (Iversen and Brun 1951). Afterwards, several instruments and methods were introduced. Nowadays, a real time ultrasound guided method has become the standard technique (Cozens et al. 1992; Marwah and Korbet 1996; Burstein et al. 1993; Nass and O’Neill 1999). It has been proved to achieve a better yield and fewer complications than the blind method (Maya et al 2007). Furthermore, a spring loaded automated gun instrument has become the instrument of choice (Burstein et al. 1993; Wiseman et al. 1990; Dowd et al. 1991). As any invasive procedure, renal biopsies carry the risk of several complications, like pain, infection and bleeding. Bleeding complications can present with drop in haemoglobin, peri-renal hematoma, hematuria or formation of arterio-venous fistulas (Meldelssohn and Cole 1995). These complications may require blood transfusion and may lead to loss of the kidney or even death. Despite the high frequency of performing renal biopsies, the exact rate of bleeding complications is still obscure (Kim et al. 1998). Many data are collected before performing a renal biopsy, trying to predict post biopsy bleeding like blood pressure, haemoglobin, bleeding time, prothrombin and coagulation. However, no study has proved that all these are important to predict occurrence of complications (Burstein et al. 1993; Marvah and Korbet 1996). Few studies have examined the complication rate of percutaneous ultrasound guided biopsies using spring loaded devices (Bogan et al. 1990; Kolb et al. 1994; Mahoney et al. 1993; Hanas et al. 1992; Mendelssohn and Cole 1995) and most of these studies have focused on this procedure using different needle sizes (Donovan et al. 1991; Kumar et al. 1992; Ogborn and Grimm 1992; Tung et al. 1992). These studies proved that rate of complications and tissue adequacy were higher while using 14G needles than while using 16G needles (Tøndel et al 1988). Several techniques have been used to perform real time ultrasound guided renal biopsies using a spring loaded automated biopsy gun. The most common are needle-guided (ultrasound-guided renal biopsy) and free-hands(ultrasound-assisted renal biopsy) techniques. However, to our knowledge, no study has evaluated the complication rate of real time ultrasound guided biopsies using the two techniques. The aim of our study was to compare the adequacy and complication rate of this procedure comparing hands-free and needle-guided real time ultrasound guided techniques. Methods and analysis Adequacy and complication rates of 527 renal biopsies performed at Lancashire teaching hospitals from January 2010 to end of June 2014 were retrospectively reviewed using a computerised database. All biopsies were performed by seven trained nephrologists. The technique of renal biopsy (ultrasound-assisted versus ultrasound-guided) was at the discretion of the operator and was based on their past experience performing the kidney biopsy. Both 14G and 16G sized needles were used with the spring-loaded automated gun (ANGIOTECH Tru-Core II Automatic Biopsy Instrument). The biopsy procedure was performed electively in a day case unit for patients suitable for the procedure on out-patient basis. Patients signed consent after the procedure had been explained to them. All patients had pre-biopsy renal ultrasound scan and coagulation test that were within normal. Pre-biopsy blood pressure was less than 160/95 for all patients on the day of the biopsy. Patients who had native kidney biopsy were positioned in prone position with a pillow under the abdomen, with the left kidney as the default site for the biopsy. Patients for transplant kidney biopsy remained in a supine position. The skin was disinfected with chloraprep solution (ChloraPrep is 2 % chlorhexidine combined with 70 % isopropyl alcohol). Blood pressure and oxygen saturation were monitored during the whole procedure. In ultrasound-assisted renal biopsy technique, the kidney was visualised under ultrasound and the skin over the lower pole of the left kidney was marked. A local anaesthesia was injected via a needle or spinal needle to anesthetise the capsule of the lower pole of the left kidney. A small incision was made in the skin and the spring loaded automated gun was used for all cases and under real-time ultrasound guidance. Number of passes in individual patients in our study were one to three passes. minor complications between free hand and needle-guided technique using 16G needles. Both techniques showed adequate tissue sampling.