Baseline immunosuppression is associated with histological findings in early protocol biopsies.
BACKGROUND
Protocol biopsies performed in stable renal allografts show different degrees of acute and chronic lesions that have been related with graft outcome. However, the utility of protocol biopsies to manage baseline immunosuppression has not been well characterized.


METHODS
We performed a case-control study to compare histological lesions observed in protocol biopsies in 49 patients treated with tacrolimus (TAC), mycophenolate mofetil (MMF), and prednisone to 49 patients treated with cyclosporine Neoral (CsA), MMF, and prednisone. Histological lesions were graded according to 1997 Banff criteria. The analysis was done according to an intention-to-treat basis.


RESULTS
Patients treated with TAC displayed in the protocol biopsy a lower acute score (0.61+/-1.01 vs. 1.26+/-1.45; P=0.0115) and a similar chronic score (1.57+/-1.97 vs. 1.51+/-1.59; P=NS). Transplant glomerulopathy was also lower in TAC treated patients (0.02+/-0.14 vs. 0.20+/-0.41; P=0.0037). Univariate and multivariate logistic regression analysis showed that the presence of acute inflammation was associated with tacrolimus treatment (relative risk [RR]: 0.30, 95% confidence interval [CI]: 0.11-0.84; P=0.0211) and the time of biopsy (RR per month: 0.56, 95% CI: 0.32-0.97; P=0.0394). The presence of chronic lesions was only associated with serum creatinine at the time of biopsy (RR: 1.01, 95% CI: 1.00-1.02; P=0.0439).


CONCLUSIONS
The incidence of inflammatory lesions and transplant glomerulopathy is lower in patients treated with TAC than in patients treated with CsA. These data suggest that baseline immunosuppression could influence the severity of histological lesions in stable grafts.
Nephrology Department, Hospital Universitari de Bellvitge, C/ Feixa Llarga s/n, 08907 L'Hospitalet, Barcelona, Spain. fmoreso@csub.scs.es
Francesc
F
Moreso
Daniel
D
Serón
Marta
M
Carrera
Salvador
S
Gil-Vernet
Josep M
JM
Cruzado
Miguel
M
Hueso
Xavier
X
Fulladosa
Rosa
R
Ramos
Meritxell
M
Ibernon
Alberto M
AM
Castelao
Josep M
JM
Grinyó
D000328:Adult; D000368:Aged; D001706:Biopsy; D016022:Case-Control Studies; D005260:Female; D006084:Graft Rejection; D006801:Humans; D007165:Immunosuppression Therapy; D007668:Kidney / Q000473:pathology*; D016030:Kidney Transplantation; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies