Duodenal histology for monitoring treatment of acute rejection in pancreaticoduodenal allografts in rats.
BACKGROUND
Although the value of duodenal histology as a means to diagnose acute rejection in pancreaticoduodenal allografts has been validated, it is not known how the duodenum responds to antirejection treatment in comparison with the pancreas.


METHODS
Diabetic Lewis rats received a pancreaticoduodenal allograft. Cyclosporine was given for 5 days and then discontinued for 2 days (group 1), for 4 days (group 2), for 6 days (group 3), for 8 days (group 4), for 9 days (group 5), and for 10 days (group 6). Two animals of each group were killed for histology at the end of immunosuppressive-free intervals. In the remaining rats, rejection was treated with methylprednisolone on 3 consecutive days. Duodenal histology was compared with pancreatic morphology before and after treatment of rejection.


RESULTS
Duodenal histology had a positive and negative predictive value of 100% for detection of acute rejection in the pancreatic portion of the graft. After antirejection treatment, duodenal morphology was however less accurate (positive predictive value, 96%; negative predictive value, 67%). The Spearman correlation coefficient (p) of duodenal and pancreatic rejection grades was higher before antirejection treatment (p=1.0) than thereafter (p=0.724). Considering interstitial and vascular changes separately, vascular rejection correlated to a higher extent than interstitial rejection between the two portions of the graft (p=0.725 vs. p=0.677).


CONCLUSIONS
Duodenal histology accurately predicts the initial diagnosis of rejection of the pancreas. However, after treatment of acute rejection, duodenal morphology is more likely to recover from rejection than the pancreas. Awareness of this phenomenon might be important for the interpretation of duodenal follow-up biopsies.
Mark
Walter
W
University Hospital Innsbruck, Department of Transplant Surgery, Anichstrasse 35, A-6020 Innsbruck, Austria. Walter.Mark@uibk.ac.at
Hechenleitner
Paul
P
Dietze
Otto
O
Klima
Günther
G
Schneeberger
Stefan
S
Steurer
Wolfgang
W
Candinas
Daniel
D
Margreiter
Raimund
R
Königsrainer
Alfred
A
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D004386:Duodenum / Q000473:pathology* / Q000637:transplantation*; D006084:Graft Rejection; D006649:Histocompatibility Antigens / Q000276:immunology; D008297:Male; D016035:Pancreas Transplantation; D051381:Rats; D011917:Rats, Inbred Lew; D014184:Transplantation, Homologous
D001786:Blood Glucose; D006649:Histocompatibility Antigens; C038353:histocompatibility antigens RT, rat