The Renal Histological Correlates of Refractory Renal Dysfunction After Liver Transplantation.

ABSTRACT

Background: Kidney dysfunction is common after liver transplantation (LT) and is often attributed to calcineurin inhibitors (CNIs). Very few studies have looked at histological causes. Material and methods: The study is a retrospective analysis of histological findings and diagnosis in all patients who underwent a kidney biopsy after LT from 2010 to 2020. Data are shown as mean ± standard deviation or medians (25-75 interquartile range). Results: The study cohort consisted of 26 patients (25 males, 1 female), aged 55 ± 7 years at the time of the kidney biopsy. Kidney biopsies were done at 27.5 (6.7-60.7) months after LT. At the time of the kidney biopsy, the median serum creatinine was 2.10 (1.50-2.86) mg/dl and proteinuria was 3.8 (1.8-5.9) gm/day. Twenty-four (92%) patients were on CNIs. The diagnoses on kidney biopsies were diabetic nephropathy (n = 7), focal segmental glomerulosclerosis (n = 4), CNI nephrotoxicity (n = 3), IgA nephropathy (n = 4), chronic glomerulonephritis (n = 3), hypertensive nephropathy (n = 1), membranous glomerulonephritis (n = 1), acute on chronic interstitial nephritis (n = 1), and C1q nephropathy (n = 1), and the sample was inadequate in one patient. A total of sixteen patients had progression of kidney disease. The kidney function remained stable/improved in 6 (23%) patients, follow-up data were not available for 4 patients. Fourteen (53.8%) patients (including one with CNI nephrotoxicity) required hemodialysis at 13.5 (5.7-29) months after the kidney biopsy. Conclusion: Although the kidney biopsy diagnosed the cause of unexplained renal insufficiency in LT recipients, the majority of patients progressed to end-stage renal disease despite treatment modifications. The use of CNIs was an uncommon cause of renal impairment.