Influence of native kidney biopsy on the decision between pancreas transplantation alone and pancreas-kidney transplantation

M. Perosa, R.A. Oliveira, H. Noujaim, L.T. Mota, J.R. Branez, L.E. Ianhez, A.P. Trevizol, J.W. Teixeira, D. Martini, D. Malheiros, T. Genzini
HEPATO, Organ Transplantation, São Paulo, Brazil

The functional tests such as creatinine clearance (CCl) or proteinuria may be erratic and inaccurate, particularly for type 1 diabetics with intermediate renal dysfunction (“gray zone“).

Objective: Establish the role of native kidney biopsy (NKB) in patients who will be submitted to pancreas transplantation (PT) and have intermediate renal dysfunction.

Methods: We analyzed 13 type 1 diabetic patients (8 female, mean age of 36 years, ranging from 26 to 60) referred to PT in whom a NKB was performed. The indication of NKB was a CCl range of 35-80ml/min and/or proteinuria >1g/24hours after several samples collected. NKB was guided by ultrasound and glomerular and interstitial fibrosis were considered as the most important and irreversible changes. A fibrosis index below 20% was considered mild and above 20% as severe kidney injury. The histological findings were correlated to the final clinical decision in each case and patients were distributed among 3 groups: A= PTA performed; B=SPK or KTA performed; C= Stand by patients (on waiting list or just being followed).

Results: The average CCl was 52.7ml/min (37-76ml/min) and proteinuria was 2.58g/24h (0.15-6.6g/24h). Eight NKB were considered severe and 5 mild. Two patients were included in Group A, 3 in B and 8 in C. In eleven patients (85%), NKB strongly influenced the final clinical decision and in 2, although a mild result was obtained, the clinical decision was against PTA due to clinical and functional deterioration during the follow-up. Importantly, in the 8 cases with severe kidney injury on NKB, a PTA was avoided and these patients were either submitted to SPK, KTA or have been at close follow-up for a future SPK.

Conclusions: NKB was very predictive of kidney evolution and strongly influenced the final clinical decision in 85% of patients assessed for PT with intermediate renal dysfunction.