Safety of Outpatient Kidney Biopsies

Kidney biopsy is frequently performed in our centre as an outpatient procedure. The aim of this study was to evaluate the safety of biopsy in the outpatient setting.

We analysed kidney biopsies performed from March 2013 to February 2017. Seven hundred twenty-five biopsies performed in the outpatient setting were identified: There were 592 transplant and 133 native biopsies including 3 solitary kidney biopsies. All were performed under ultrasound guidance using a 16G or 18G needle, with freehand technique. In all patients with estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 desmopressin was administered. Patients were observed for 6h before discharge, with a complete blood count and urine test after 4 h. Major complications were haemorrhage requiring therapeutic intervention or transfusion. Minor complications were significant reduction in haemoglobin (Hb) levels (>10%), without need for transfusion or intervention and macrohaematuria.

There were 506 (69.8%) male patients. Average age was 50.3 ± 12.7 years. Indications for native kidney biopsy included nephrotic syndrome (39.8%), nephritic syndrome (42.9%), follow-up biopsy (15.8%), and other (1.5%). There were no major complications. A decline in Hb was observed in 72% of patients. Average Hb decline was 4.2 ± 6.3 g/L. In 10.1% patients there was >10% reduction in Hb level, with no evident bleeding, including by ultrasonography. In 2.5% of patients, macrohaematuria was present. In a multivariate analysis, male gender, lower eGFR, higher pre-biopsy Hb and native kidney biopsy were predictive for Hb decline. No therapeutic interventions were required.

We found that kidney biopsy performed in an outpatient setting in select patients is only rarely associated with adverse events and is a safe procedure.