**4. Appraisal of the methods**

The image guided percutaneous techniques are successful in terms of tissue yield in majority of cases. Furthermore, image guidance is particularly instrumental to the safe performance of focus biopsies in cases of cystic kidneys and solid renal masses [9]. Apart from methods described earlier, newer imaging techniques, such as, CT fluoroscopy and fusion ultrasonography may apply to renal biopsy in the future [15].

Percutaneous ultrasound guided approach is standard care for biopsy of nonfocal lesions [7]. The real-time ultrasound guided technique has been compared to the blind technique after localisation with ultrasound, and no significant difference in tissue yield was noted [16]. Both techniques have similar potential complications and can be used in similar patients. The rates of complications associated with PRB are difficult to compare across studies because of the heterogeneity of studies in terms of technique and needle used, operator and definitions of complications, e.g. bleeding [7]. These procedures are however done routinely without need for overnight admission except severe complications arise.

Tissue diagnosis may not be successful in about 6% of ultrasound guided biopsies in some series and common reasons are due to operator's technique, type/ size of biopsy needle, and patient factors (reduced GFR, small atrophic kidneys,

anatomically complex kidneys). Some comparative studies have reported that automated needles provide superior yield and lower major complication rates than older, hand-driven (Tru-Cut) systems [17, 18]. A 14- or 16-gauge needle provides larger cores and the tissue yields are comparable however, the 14-gauge needle is reportedly associated with more bleeding complications [19, 20]. The 18-gauge needle on the other hand is smaller and some studies report a lower tissue yield [19, 20]. A study by Kriegshauser et al. found that operator experience, taking multiple specimens, and using the cortical tangential approach significantly improved the pathologic material obtained during native renal biopsies [21]. It also helps to have a light microscope available during renal biopsy procedure, to visualize biopsy core immediately after it is obtained.

The CT-guided method can be used in obese patients and other patients who are unable to lay prone, patients with complex anatomy, and when the kidneys are not sufficiently visualised by ultrasound scan [8]. This procedure has been associated with 100% success in some reports [22]. Biopsy of focal lesions is more successful with CT-guidance using either core biopsy or aspiration needle, although some authors have reported increased diagnostic yield when a combination of both needles are used [9]. Unlike the ultrasound-guided technique, it is not performed real-time and patients are exposed to some radiation. Most patients will usually require conscious sedation but can be discharged a few hours after the procedure provided there are no major complications.

Contraindications to PRB such as uncontrolled severe hypertension, morbid obesity, uncontrolled bleeding diathesis, solitary kidney, small kidneys, complex kidney anatomy (e.g. high location, horse-shoe kidney), and renal impairment; are often reasons for selection of alternative techniques. Additionally, failed percutaneous biopsy, poor visualization on imaging, cystic kidney with rapidly progressing GN, and high location of the kidneys are some indications for a laparoscopic or open biopsy [13]. The major advantages of the laparoscopic and open biopsy techniques are the opportunity for direct visualization of the kidney and good intra-operative haemostatic control of the biopsy site [13]. The tissue yield is often abundant and diagnostically useful, however the risks of general surgery/anaesthesia, need for special surgical skill, overnight admissions and high costs are some of the disadvantages.

The transjugular technique is most popular for combined liver and kidney biopsy, and in patients with certain contraindications to PRB (bleeding, inability to lie prone due to obesity, ascites or respiratory difficulty) in whom pathological diagnosis might alter clinical management. Diagnostic yield is comparable with PRB, but differs slightly depending on the approach used, 73–95% diagnostic yield has been reported for the aspiration needle approach [23–26] compared with 89–96.5% for the core biopsy needle [27, 28]. Although judged to be a safe and efficient procedure, there is the risk of contrast induced nephropathy and capsular perforation, which might require coil embolisation. Major complications are seen in 1–18% of cases when using the aspiration needle [23–26], compared to 2.7–27% with the core biopsy technique [27, 28]. Rathod et al. in India reported capsular perforation in five out of nine patients who had TRJRB using the core biopsy approach, although none had major event requiring intervention (blood transfusion or embolisation) [11]. Contrast nephropathy is a concern given that a significant proportion of patients undergoing this procedure have baseline renal impairment, but only 15–30 ml of contrast is used. There is usually no need for overnight stay as patient can be discharged as early as 4 hours post procedure.

Finally, regardless of the renal biopsy method selected, the nephrologist must ensure adequate pre- and post-care of the patient and obtain informed consent. Biopsy protocols should ideally exist in every centre carrying out renal biopsies,

**21**

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

competent pathologists.

**Acknowledgements**

**Conflict of interest**

**Author details**

Ogochukwu Okoye

determine the safety and efficacy of the procedure.

The author declares no conflict of interest.

**5. Conclusion**

and should be strictly adhered to. It is standard practice before kidney biopsies to check patient's vital signs, obtain a complete blood count, international normalized ratio/prothrombin time, activated partial thromboplastin time, serum creatinine, urine culture, and group/crossmatch blood. Medications should be reviewed for drugs that may increase bleeding risk. Intravenous access is needed and anxious, uncooperative, and/or pediatric patients may require conscious sedation or general anesthesia. Biopsy tissue histology must only be interpreted by experienced and

Renal biopsy can be an indispensable tool in the diagnosis, monitoring, treatment, and prognosis, of patients with non-focal or focal renal parenchymal disease or systemic diseases with renal manifestation. The diagnostic usefulness significantly depends upon the operator's ability to select and prepare the patient based on in depth knowledge of the indications, contraindications and complications. The operator's skill, choice of technique and instruments are key factors that will

H3Africa Kidney Research Network, for providing my division with training and

equipment support for percutaneous ultrasound guided renal biopsy.

Department of Internal Medicine, Delta State University, Abraka, Nigeria

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: ogonwosu2002@yahoo.com

provided the original work is properly cited.

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

and should be strictly adhered to. It is standard practice before kidney biopsies to check patient's vital signs, obtain a complete blood count, international normalized ratio/prothrombin time, activated partial thromboplastin time, serum creatinine, urine culture, and group/crossmatch blood. Medications should be reviewed for drugs that may increase bleeding risk. Intravenous access is needed and anxious, uncooperative, and/or pediatric patients may require conscious sedation or general anesthesia. Biopsy tissue histology must only be interpreted by experienced and competent pathologists.
