Renal interstitial fibrosis in 0-hour biopsy as a predictor of post-transplant anemia

Background/Aims: Anemia is common in kidney transplant patients and may cause adverse cardiovascular events. Several studies have reported some predictors of post-transplant anemia. However, associations between the pathological findings in the 0-hour biopsy and anemia have not been well described. Methods: 258 consecutive kidney transplant patients were enrolled in this retrospective study. The patients were divided into two groups, according to the presence or absence of interstitial fibrosis and tubular atrophy (IF/TA) in the 0-hour biopsy: the IF/TA group with fibrotic area ≥5% (n = 131) and the non-IF/TA group with fibrotic area <5% (n = 127). We examined the association between IF/TA and post-transplant anemia. Results: Serial changes in hemoglobin levels in the IF/TA group were lower than in the non-IF/TA group (p = 0.007). Anemia at 12 months was found in 53% of the IF/TA group, and 35% of the non-IF/TA group (p = 0.004). Even after adjustment for several confounders including graft function, the presence of IF/TA was independently associated with post-transplant anemia at 12 months (odds ratio 1.88, 95% confidence interval 1.06-3.36, p = 0.031). This association was still significant in a subgroup with normal graft function. Conclusions: IF/TA in the 0-hour biopsy specimen is one of the predictors for post-transplant anemia and can be used to identify patients who need the treatment with erythropoiesis-stimulating agents.