Ultrasound Guided Percutaneous Renal Biopsy Using 18-Gauge versus 16-Gauge Needles in Native Kidneys with Diffuse Renal Disease: Comparison Regarding Sample Adequacy and Complication Rates

Abstract Background Regardless of the advancements made in non-invasive diagnostic tools, Percutaneous Renal Biopsy (PRB) remains the corner stone for reaching a reliable diagnosis for most renal parenchymal diseases. Needle gauge is a key variable in determining the adequacy and therefore success of renal biopsy as it influences the number of glomeruli obtained in the sample. To date, there is still much debate over the appropriate needle size to use when trying to balance between meeting diagnostic requirements; whilst decreasing the incidence of complications. At present, 16G needles or 18G needles are used for percutaneous renal biopsy at our institute on basis of personal preference and experience, but there is still controversy about the effect and safety of 18G and 16G biopsy needles in terms of the two different diameters, with no irrefutable evidence to dictate the superiority of one needle gauge over the other within the present literature. This study was the first in the Middle East to address the effect of using different gauge needles on sample adequacy and complication rates in real-time US guided PRB. Objective To compare sample adequacy and complication rates between US guided PRB acquired using 16- Gauge versus 18- Gauge needles. Patients and Methods This study was a prospective study conducted at the Interventional Radiology (IR) Unit at Ain Shams University Tertiary Hospitals from December 2022 till April 2023, on a series of 60 patients who visited our radiology suite to undergo renal biopsy, with a total of 62 renal biopsies. The patients were randomly allocated into two separate groups based on the biopsy needle gauge that was used to retrieve their renal biopsy sample. Results This study showed that a 16G biopsy needle has no obvious advantage over an 18G needle in terms of the number of glomeruli and the adequate sample rate. Although the frequency of overall complications as well as major complications was higher in 16 G in comparison to 18 G group this difference was statistically non-significant yet held clinical implication. Conclusion The 18G needle appears to be as effective as the 16G for percutaneous renal biopsy regarding sample adequacy, with clinically significant lower rate of major complications.