title: Bleeding complications of native kidney biopsy: a systematic review and meta-analysis.
abstract: BACKGROUND
  Kidney biopsy provides important information for nephrologists, but the risk of complications has not been systematically described.
  
  
  METHODS
  Meta-analysis of randomized controlled trials and prospective or retrospective observational studies.
  
  
  METHODS
  Adults undergoing native kidney biopsy in an inpatient or outpatient setting.
  
  
  METHODS
  MEDLINE indexed studies from January 1980 through June 2011; sample size of 50 or more.
  
  
  METHODS
  Native kidney biopsy with automated biopsy device and real-time ultrasonographic guidance.
  
  
  RESULTS
  Macroscopic hematuria and erythrocyte transfusion rates and factors associated with these outcomes.
  
  
  RESULTS
  34 studies of 9,474 biopsies met inclusion criteria. The rate of macroscopic hematuria was 3.5% (95% CI, 2.2%-5.1%), and erythrocyte transfusion was 0.9% (95% CI, 0.4%-1.5%). Significantly higher rates of transfusion were seen with the following: 14-gauge compared with smaller needles (2.1% vs 0.5%; P = 0.009), studies with mean serum creatinine level ≥2.0 mg/dL (2.1% vs 0.4%; P = 0.02), ≥50% women (1.9% vs 0.6%; P = 0.03), and ≥10% of biopsies for acute kidney injury (1.1% vs 0.04%; P < 0.001). Higher transfusion rates also were observed in studies with a mean age of 40 years or older (1.0% vs 0.2%; P = 0.2) and mean systolic blood pressure ≥130 mm Hg (1.4% vs 0.1%; P = 0.09). Similar relationships were noted for the macroscopic hematuria rate with the same predictors, but none was statistically significant.
  
  
  CONCLUSIONS
  Publication bias, few randomized controlled trials, and missing data.
  
  
  CONCLUSIONS
  Native kidney biopsy using automated biopsy devices and real-time ultrasonography is associated with a relatively small risk of macroscopic hematuria and erythrocyte transfusion requirement. Using smaller gauge needles may lower complication rates. Patient selection may affect outcome because studies with higher serum creatinine levels, more women, and higher rates of acute kidney injury had higher complication rates. Future studies should further evaluate risk factors for complications.
authors.affiliation: Department of Medicine, Boston University Medical Center, MA 02118, USA.
authors.forename: Kristin M
authors.initials: KM
authors.lastname: Corapi
authors.forename: Joline L T
authors.initials: JL
authors.lastname: Chen
authors.forename: Ethan M
authors.initials: EM
authors.lastname: Balk
authors.forename: Craig E
authors.initials: CE
authors.lastname: Gordon
mesh_terms: D000328:Adult; D001707:Biopsy, Needle / Q000009:adverse effects* / Q000295:instrumentation; D003404:Creatinine / Q000097:blood; D004867:Equipment Design; D006417:Hematuria / Q000209:etiology*; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology*; D009339:Needles; D012307:Risk Factors; D014463:Ultrasonography
chemical_list: D003404:Creatinine