Renal histological lesions and outcome in liver transplant recipients

Background: Chronic kidney disease in liver transplant (OLT) recipients is often attributed to calcineurin inhibitors (CNI) toxicity, but little is known about the spectrum of their renal histological lesions. Methods: Between 1988 and 2008, 1698 OLTs were performed in our center. We retrospectively analyzed clinical and histological data on 23 recipients (1.4%) referred for kidney biopsy (KB). Results: Median age at OLT was 50.2yr, 65.2% were men, 30.4% had hepatitis C, and 95.7% were given CNI. KB was performed 6.9yr (median) post-OLT. Median creatinine was 1mg/dL pre-OLT and 2.2mg/dL at KB. Main pathological diagnoses were focal segmental and global glomerulosclerosis (n=8, 34.8%), glomerular diseases (7, 30.4%), CNI toxicity (2, 8.7%), and diabetic nephropathy (2, 8.7%). Moderate/severe interstitial fibrosis, tubular atrophy, arteriosclerosis, and hyalinosis were present in 47.8%, 43.5%, 60.9%, and 56.5%, respectively. Twelve patients (52.5%) reached end-stage renal disease (ESRD) and 17 (73.9%) died. Death was more common among those reaching ESRD, but the difference was not significant (83.3% vs. 63.6%, p=0.37). Conclusion: Renal histology is variable and not limited to CNI toxicity in OLT recipients referred for KB. Whether management based on KB findings can directly improve outcomes remains unclear.