Comparison of jejunal and ileal surveillance biopsies in a porcine model of intestinal transplantation

Background. The optimal biopsy site of bowel allografts for rejection surve illance remains controversial. We compared the results of jejunal (JBx) and heal (IBx) biopsies after bowel transplantation in a porcine model. Methods. Eighteen Yorkshire-Landrace pigs served as donors. Eighteen recipi ent pigs underwent total enterectomy followed by orthotopic small bowel tra nsplantation with or without the colon. A jejunostomy and a Bishop-Koop ile ostomy were constructed for biopsies, Immunosuppression consisted of FK506 (target level 10-15 ng/ml by enzyme immunoparticle assay) and prednisone ad ministered via the jejunostomy. Simultaneous JBx and IBx were performed twi ce weekly. Acute rejection was graded as mild, moderate, or severe based on previously published criteria. Results. Mean overall survival after the transplant was 17.4 days. A total of 162 specimens were collected and evaluated for rejection (JBx, 81; IBx, 81). Acute rejection was detected in 41 JBx cases (50.7%) and 40 IBx cases (49.4%). The presence or absence of rejection was concordant between JBx an d IBx in 70 of 81 case pairs (86.4%). Of the 11 discordant case pairs, 6 we re JBx positive/IBx negative, whereas 5 were JBx negative/IBx positive, A t otal of 35 case pairs were synchronously positive, 24 (68.8%) of which demo nstrated the same degree of rejection, Conclusions. The correlation between JBx and IBx of bowel allografts in dia gnosing the presence of acute rejection is quite good. However, performing IBx alone would have missed about 7.5% of the rejection episodes. Because t he early treatment of rejection in bowel transplantation is of paramount im portance, in selected cases, biopsies from both the ileum and jejunum shoul d be considered if technically feasible.