title: The value of post-biopsy ultrasound in predicting complications after percutaneous renal biopsy of native kidneys.
abstract: BACKGROUND
  Clinically significant bleeding complications occur in >30% of patients undergoing percutaneous renal biopsy (PRB) of native kidneys and can be severe in up to 10% of patients. A noninvasive measure that would reliably predict which patients will do well with an uncomplicated post-biopsy course or which patients may be at risk of developing a clinically significant complication is in great demand.
  
  
  METHODS
  PRB of native kidneys was performed in 162 adult patients from February 2002 through February 2007 using real-time ultrasound and automated needle. Renal ultrasound (US) was performed at 1-h post-PRB to assess biopsy-related bleeding. Patients were observed for 24 h post-PRB to monitor clinically apparent biopsy-related complications. The value of the post-biopsy ultrasound in predicting complications was assessed.
  
  
  RESULTS
  A clinically apparent complication was observed in 26 (16%) patients post-PRB (13 minor not requiring any intervention and 13 major requiring intervention). In patients with complicated courses, a haematoma at 1 h was seen in 77% (69% with minor and 87% with major complications). However, only 27 (20%) of 136 patients without complications (P < 0.0001) had a haematoma at 1 h. The presence of a haematoma 1-h post-PRB had a sensitivity of 77%, specificity of 80%, positive predictive value of 43% but a negative predictive value of 95% for predicting clinical complications.
  
  
  CONCLUSIONS
  We find that with the use of renal ultrasound 1-h post-PRB, the absence of perinephric bleeding is predictive of an uncomplicated course while the presence of a perinephric haematoma is not reliably predictive of a clinically significant complication post-renal biopsy.
authors.affiliation: Section of Nephrology, Department of Medicine, Rush University Medical Center, Chicago, IL 60612, USA.
authors.forename: Bryan
authors.initials: B
authors.lastname: Waldo
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Korbet
authors.forename: Maija G
authors.initials: MG
authors.lastname: Freimanis
authors.forename: Edmund J
authors.initials: EJ
authors.lastname: Lewis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle / Q000009:adverse effects*; D002648:Child; D005260:Female; D006406:Hematoma / Q000000981:diagnostic imaging* / Q000209:etiology; D006470:Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging* / Q000473:pathology*; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D055815:Young Adult