title: Pretransplant biopsy in expanded criteria donors: do we really need it?
abstract: BACKGROUND
  Renal transplantation is the best treatment for end-stage renal disease, including when using expanded criteria donors (ECD) kidneys. However, these suboptimal kidneys should be evaluated rigorously to meet their usefulness. Opinions differ about the best way to evaluate them.
  
  
  METHODS
  We retrospectively reviewed kidneys from ECD harvested by a single academic institution between January 2008 and September 2013. Needle biopsies were performed at the time of the harvest when considered relevant by the transplant team. Two pathologists where responsible for their analysis; the Remuzzi classification has been used in all cases.
  
  
  RESULTS
  We evaluated 560 ECD kidneys. Biopsies were made in 197 (35.2%) organs, 20 of which were considered not usable and 36 good only for double transplantation. Sixty-three kidneys (11.3%) were discarded by the transplant team based on the biopsy result and clinical criteria. Donors who underwent a biopsy were older (P < .001) and had a worse glomerular filtration rate (GFR; P = .001). Comparing donors approved and rejected by the biopsy, the rejected donors were heavier (P = .003) and had a lower GFR (P = .002). Cold ischemia time was longer for the biopsy group (P < .001). Regarding graft function, the biopsy overall score correlated with the transplant outcome in the short and long term. Separately, glomeruli and interstitium scores were correlated with recipient's GFR in the earlier periods (3 months; P = .025 and .037), and the arteries and tubules correlated with GFR in the longer term (at 3 years P = .004 and .010).
  
  
  CONCLUSIONS
  The decision on the usability of ECD grafts is complex. At our center, we chose a mixed approach based on donor risk. Low-risk ECD do not require biopsy. In more complex situations, especially older donors or those with a lower GFR, prompted a pretransplant biopsy. The biopsy results proved to be useful as they relate to subsequent transplant outcomes, thereby allowing us to exclude grafts whose function would most probably be less than optimal.
authors.affiliation: Urology and Renal Transplantation Department, Coimbra's Hospital and University Center, Coimbra, Portugal. Electronic address: edsilva.elv@gmail.com.
authors.forename: E
authors.initials: E
authors.lastname: Tavares da Silva
authors.affiliation: Pathology Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: R
authors.initials: R
authors.lastname: Oliveira
authors.affiliation: Urology and Renal Transplantation Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: D
authors.initials: D
authors.lastname: Castelo
authors.affiliation: Urology and Renal Transplantation Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: V
authors.initials: V
authors.lastname: Marques
authors.affiliation: Pathology Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: V
authors.initials: V
authors.lastname: Sousa
authors.affiliation: Pathology Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: P
authors.initials: P
authors.lastname: Moreira
authors.affiliation: Urology and Renal Transplantation Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: P
authors.initials: P
authors.lastname: Simões
authors.affiliation: Pathology Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: C A
authors.initials: CA
authors.lastname: Bastos
authors.affiliation: Urology and Renal Transplantation Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Figueiredo
authors.affiliation: Urology and Renal Transplantation Department, Coimbra's Hospital and University Center, Coimbra, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Mota
mesh_terms: D000368:Aged; D001706:Biopsy / Q000379:methods*; D005260:Female; D005919:Glomerular Filtration Rate; D006085:Graft Survival; D006801:Humans; D007668:Kidney / Q000473:pathology* / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D057234:Preoperative Period; D012189:Retrospective Studies; D014019:Tissue Donors