Plasma-cell-rich infiltrates in paediatric renal transplant biopsies are associated with increased risk of renal allograft failure

Increased plasma cell infiltration in renal allograft biopsies is a rare finding associated with poor outcome in adult renal transplant recipients. The clinical impact of increased plasma cell infiltrates in paediatric renal transplant recipients (pRTR) remains unknown.

We conducted a retrospective case–control study from April 1996 to March 2014 comparing the outcome of pRTR with increased (>10 % of infiltrate) plasma cells in renal transplant biopsies to a control cohort of pRTR without increased plasma cell infiltration but similar grade of rejection according to Banff classification.

Increased plasma cell infiltrates were present in 14 of 162 (9 %) reviewed pRTR aged 3.2–17.5 (median 13.4) years at time of transplantation. Compared with 14 pRTR renal transplant biopsies without significantly increased plasma cells, there were no significant differences in mismatch and baseline estimated glomerular filtration rate (eGFR). Plasma cells were present in case biopsies at a maximal density of 14–116 (median 33) plasma cells/HPF. Increased plasma cells were associated with decreased eGFR at biopsy (22 vs. 49 ml/min/1.73 m²; p < 0.001) and 4 weeks post-biopsy (26 vs. 56 ml/min/1.73 m²; p < 0.001) despite comparable eGFR 4 weeks prior to biopsy. Increased plasma cells were further associated with significantly increased frequency of renal allograft loss (71 % vs. 7 %; p < 0.001) at 0–27 (median 2) months after biopsy.

Increased plasma cell infiltrates in pRTR are uncommon but associated with significantly reduced renal allograft survival as well as significantly reduced allograft function in surviving grafts.