BACKGROUND: Recurrence of diabetic kidney disease (DKD) after diabetic kidney transplantation has been reported. The aim of this study was to determine the early histologic lesions, focusing especially on abnormal glomerular angiogenesis, and clinical risk factors of recurrent DKD after kidney transplantation. METHODS: The authors studied 34 renal transplant recipients with diabetes and 30 without diabetes. All patients had undergone both baseline and posttransplant follow-up biopsies. Glomerular morphometric analyses of the mesangial area, the capillary number, and the capillary area were performed with a computer-assisted image analyzer, and glomerular basement membrane (GBM) thickness was evaluated by electron microscopy. The incidence of polar vasculosis as an angiogenic phenomenon was also evaluated. Clinical data including hemoglobin (Hb)A1c, blood pressure, urinary albumin excretion, and serum lipid profiles were compared with histologic parameters. RESULTS: Together with the increased glomerular mesangial area and GBM thickness, the glomerular capillary number and area and the incidence of polar vasculosis were significantly higher in patients with diabetes. Most of these alterations were significantly associated with the mean posttransplant HbA1c levels but not with blood pressure or lipid profiles. In the multiple regression analysis, HbA1c level remained significantly associated with these histologic parameters. CONCLUSIONS: Similar to mesangial expansion and GBM thickening, glomerular neovascularization represented by increased capillary number and area and glomerular polar vasculosis can occur as an early diabetic lesion in recurrent DKD. Posttransplant hyperglycemia is a significant risk factor predictive of the progression of recurrent DKD in kidney allografts.
BACKGROUND: Recurrence of diabetic kidney disease (DKD) after diabetic kidney transplantation has been reported. The aim of this study was to determine the early histologic lesions, focusing especially on abnormal glomerular angiogenesis, and clinical risk factors of recurrent DKD after kidney transplantation. METHODS: The authors studied 34 renal transplant recipients with diabetes and 30 without diabetes. All patients had undergone both baseline and posttransplant follow-up biopsies. Glomerular morphometric analyses of the mesangial area, the capillary number, and the capillary area were performed with a computer-assisted image analyzer, and glomerular basement membrane (GBM) thickness was evaluated by electron microscopy. The incidence of polar vasculosis as an angiogenic phenomenon was also evaluated. Clinical data including hemoglobin (Hb)A1c, blood pressure, urinary albumin excretion, and serum lipid profiles were compared with histologic parameters. RESULTS: Together with the increased glomerular mesangial area and GBM thickness, the glomerular capillary number and area and the incidence of polar vasculosis were significantly higher in patients with diabetes. Most of these alterations were significantly associated with the mean posttransplant HbA1c levels but not with blood pressure or lipid profiles. In the multiple regression analysis, HbA1c level remained significantly associated with these histologic parameters. CONCLUSIONS: Similar to mesangial expansion and GBM thickening, glomerular neovascularization represented by increased capillary number and area and glomerular polar vasculosis can occur as an early diabetic lesion in recurrent DKD. Posttransplant hyperglycemia is a significant risk factor predictive of the progression of recurrent DKD in kidney allografts.