Correlation between the biopsies in marginal donor kidneys for transplantation: is it necessary to biopsy both kidneys?

OBJECTIVES

The objective of this study was to analyze the correlation between histological findings in both transplanted kidneys from marginal donors.

METHODS

We retrospectively reviewed the histological information on 92 kidneys obtained between January 2001 and January 2004, corresponding to 46 marginal donors. Criteria for biopsy were age greater than 55 years, hypertension, diabetes, and proteinuria. Scores were established by the pathologist including glomerulosclerosis, tubular atrophy, interstitial fibrosis, and arteriosclerosis. The score for each lesion was classified as 0 if absent; 1 if <20%; 2 if >20% and <50%; and 3 if >50%. Finally, we defined an index of renal severity damage (RSD) in order to classify the kidneys for single transplantation (0), double transplantation (1), and unsuitable for transplantation (2).

RESULTS

Of the kidneys studied, 82.6% of both kidneys showed similar degrees of glomerulosclerosis (<20% in 71.7% and >20% in 10.9%), while 17.4% showed discrepancies (> vs <20%; P=.008). On the other hand, RSD correlated in 82.6% of both kidneys (in 69.6% RSD=0; in 8.7% RSD=1; and in 4.3% RSD=2), while 17.4% showed discrepancies (P=.001). In one case (2.2%), a great discrepancy was observed; one kidney was valid for single transplantation, and the other one not valid for any transplantation, single or double.

CONCLUSIONS

This study demonstrated a correlation between the biopsy findings in both kidneys in 82.6% of marginal organ donors. However, in 17.4% of cases we observed discrepancies. The degree of glomerulosclerosis seemed to be a powerful parameter to define renal severity damage. According to these results we would recommend biopsy of both kidneys.