Live donor renal transplantation in patients with end-stage renal failure due to IgA nephropathy: clinicopathological assessment

Abstract

The long-term outcome was evaluated, in terms of recurrence and graft survival, after live donor renal transplantation in 90 grafts in 89 patients with biopsy-proven IgA nephropathy (IgAN) as a primary diagnosis of end-stage renal disease. Additionally, histological assessment including glomerular morphometry was performed in 19 grafts having recurrent IgAN. The 10-year graft survival for IgAN patients was 66%, which was comparable with that of 84% for 107 reference recipients having other kinds of glomerulonephritis (GN) or 69% for 90 other recipients having non-GN renal failure (P = 0.27). In 43 grafts, 54 event graft biopsies were performed, and mesangial IgA deposits were documented in 19 grafts. In eight grafts, lesions were accompanied by chronic rejection (CR). Ten-year cumulative recurrence was 44%. In total, 10 grafts were lost: this was due to CR (n = 3) or acute rejection (n = 1) in 24 recurrence-free recipients; CR (n = 2) or recurrence (n = 2) in 19 patients with recurrence; and patient death (n = 2) in 46 patients who did not have graft biopsy. No difference in 10-year graft survival between the patients with and without recurrence (63%vs 74%; P = 0.98), or the proportion of related donors was found (68%vs 83%; P = 0.25). In the grafts with recurrence, renal histological damage was relatively mild and had no uniform pattern. The percentage of global and segmental sclerosis were 11.9% and 3.7%, respectively. Non-sclerotic glomeruli were ischaemic or hypertrophied. Mesangium showed lysis or focal and mild expansion by matrix and cellular increase. Glomerular morphometry was performed in seven patients, in whom glomerular hypertrophy was found as demonstrated by increases of Bowman's and glomerular tuft areas (1.4 and 1.3 times the control, respectively) and concomitant decrease of total glomerular and mesangial cells per glomerular cross-section (71.2% and 84.9% of the control, respectively). In conclusion, recurrence increased to 44% with longer follow up, but this did not limit the graft outcome. Recurrence was not affected by the types of live donor. Glomerular hypertrophy in the recurrent IgAN group suggests hyperfiltration.