title: Multiple biopsy passes and the risk of complications of percutaneous liver biopsy.
abstract: OBJECTIVE
  To minimize the sample variability of liver biopsy, the tissue length should be at least 25 mm. Consequently, more than one biopsy pass is needed with cutting biopsy needles. We aimed to investigate the risk factors of biopsy-related complication, including the number of biopsy passes.
  
  
  METHODS
  All consecutive liver biopsies performed between 2005 and 2014 were included. Biopsies were ultrasound assisted and performed with cutting biopsy needles. A complication was an event where the patient visited a healthcare provider because of biopsy-related complaints. Complications followed by hospitalization 2 or more days or intervention were considered severe.
  
  
  RESULTS
  In total, 1806 liver biopsies were analyzed. Overall, 102 (5.6%) complications were observed, of which 31 (1.7%) were severe. One (0.06%) patient died. Common complications were pain (n=75/102; 74%) and bleeding (n=34/102; 33%). Two biopsy passes were not associated with an increased risk of complications compared with one biopsy pass [odds ratio (OR): 1.59; 95% confidence interval (CI): 0.83-3.04; P=0.16], whereas three or more biopsy passes increased this risk compared with one (OR: 2.97; 95% CI: 1.38-6.42; P=0.005) or two biopsy passes (OR: 1.87; 95% CI: 1.10-3.19; P=0.021). The risk of severe complications was not influenced by the number of biopsy passes (P>0.24). Hepatic malignancy (OR: 3.21; 95% CI: 1.18-8.73; P=0.022) and international normalized ratio 1.4 or more (OR: 7.03; 95% CI: 2.74-18.08; P<0.001) were risk factors of severe complications.
  
  
  CONCLUSIONS
  Severe complication rate and mortality were low. Performing multiple biopsy passes was not associated with severe complications, whereas hepatic malignancy or elevated international normalized ratio were associated with an increased risk.
authors.affiliation: aDepartment of Gastroenterology and Hepatology, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands bDepartment of Gastroenterology and Hepatology, AZ Nikolaas, Sint-Niklaas, Belgium cToronto Centre for Liver Disease, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Heng
authors.initials: H
authors.lastname: Chi
authors.forename: Bettina E
authors.initials: BE
authors.lastname: Hansen
authors.forename: Wing Yin
authors.initials: WY
authors.lastname: Tang
authors.forename: Jeoffrey N L
authors.initials: JN
authors.lastname: Schouten
authors.forename: Dave
authors.initials: D
authors.lastname: Sprengers
authors.forename: Pavel
authors.initials: P
authors.lastname: Taimr
authors.forename: Harry L A
authors.initials: HL
authors.lastname: Janssen
authors.forename: Robert J
authors.initials: RJ
authors.lastname: de Knegt
mesh_terms: D000328:Adult; D001707:Biopsy, Needle / Q000009:adverse effects* / Q000379:methods; D001777:Blood Coagulation; D016009:Chi-Square Distribution; D005260:Female; D006470:Hemorrhage / Q000209:etiology; D006760:Hospitalization; D006801:Humans; D019934:International Normalized Ratio; D008099:Liver / Q000473:pathology*; D008107:Liver Diseases / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D008113:Liver Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000473:pathology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010146:Pain / Q000209:etiology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D062606:Tertiary Care Centers