A Color Flow Tract in Ultrasound‐Guided Random Renal Core Biopsy Predicts Complications

Abstract

ObjectivesTo determine patient and procedural risk factors for major complications in ultrasound (US)‐guided random renal core biopsy.MethodsRandom renal biopsies performed by radiologists in the US department at a single institution between 2014 and 2018 were retrospectively reviewed. The patient's age, sex, race, and estimated glomerular filtration rate (eGFR) were recorded. The biopsy approach, needle gauge, length of cores, number of throws, and presence of a color flow tract were recorded. Outcome data included minor and major complications. Associations between variables were tested with χ2 analyses and univariable/multivariable logistic regression models.ResultsA total of 231 biopsies (167 native and 64 allografts) were reviewed. There was no significant difference in the sex, age, race, or eGFR between native and allograft groups. The overall rate for any complication was 18.2%, with a 4.3% rate of major complications, which was significantly greater in native compared to allograft biopsies (6% versus 0%; P = .045). A risk analysis in native biopsies only showed that major complications were significantly associated with a low eGFR such that patients with stage 4 or 5 kidney disease had higher odds of complications (odds ratio [95% confidence interval]: stage 4, 9.405 [1.995–44.338]; P = .0393; stage 5, 10.749 [2.218–52.080]; P = .0203) than patients with normal function (eGFR >60 mL/min). The presence of a color flow tract portended a 10.7 times greater risk of having any complication (95% confidence interval, 4.595–24.994; P < .001). Other procedural factors were not significantly associated with complications.ConclusionsThere is an increased risk of major complications in US‐guided random native kidney biopsy in patients with a low eGFR (<30 mL/min) and a patent color flow tract in the immediate postbiopsy setting.

Ultrasound‐Guided Thrombin Injection for the Treatment of Bleeding Following Kidney and Liver Biopsies

“…A patent track that persists for 5 minutes after percutaneous liver biopsy was found to be strongly predictive of clinically significant post biopsy bleeding 15 . If a patent color flow track is identified after native kidney biopsy there is a reported increased risk for major complications, particularly in the setting of low glomerular filtration rate 36 . An association has also been identified between a patent biopsy track (referred to as the color Doppler “line sign”) and hematomas in patients following radiofrequency ablation of liver and kidney tumors 37 .…”

Point of Care Ultrasound in Monitoring of Post-Renal Biopsy Bleeding

“…In patients who do have clinically significant complications, hematomas are noted by 1 hour post biopsy in 77% of cases and were measured at >3cm in greater than 50% of cases [3]. Presence of a color tract on doppler has also been shown to be 10.7 times more likely to result in major and minor complications [6].…”