P234
Early allograft biopsy following renal transplantation in children
Gurreebun BF, Lee CY, Roberts D, Plant ND, Webb NJ, Shenoy M.
Department of Paediatric Nephrology, Royal Manchester Children’s Hospital.
Introduction: Following publication of the TWIST Study in 2009, our centre adopted an early
steroid withdrawal (ESW) immunosuppression protocol following renal transplantation (RT).
The aims of this study were to both investigate the frequency of allograft biopsies and to assess
the rate of acute rejection (AR) within the first month following RT before and after the change
in immunosuppression protocol.
Methods: A retrospective record review of 98 consecutive transplants in 96 children between
January 2007 and August 2013 was undertaken. Tacrolimus trough levels of 10-15 µ/l were
aimed for in the first 21 days and levels of 8-10 µ/l from day 21 to 30 following RT. Indication
for biopsy was a 20% rise in plasma creatinine in the absence of infection, dehydration,
obstruction and high tacrolimus levels.
Results: Sixty four percent of kidneys were from living donors and 50% of the patients had a
favourable mismatch with no mismatch at DR. There were 33 children in the steroid group and
65 in the ESW group. Fifty three biopsies were carried out in the first month in 43 patients.
Mean timing of biopsy was 13 days following RT. Eight children had AR, giving an AR rate of
9.2% (Banff Ia in 5, Ib in 2 and IIa in 1). Nine had biopsy changes consistent with acute tubular
necrosis and seven had evidence of donor vascular disease, though no other abnormalities.
Mean eGFR peaked at 100ml/min/1.73m2 (95% CI 87-112) on day 6 and decreased to
82ml/min/1.73m2 (95% CI 71-93) by day 13 following RT. Mean tacrolimus trough level
peaked at 11.6 µ/l (95% CI 10.1-13.0) on day 10. (Figure 1)
In the steroid group, 24% of patients had an early transplant biopsy, compared to 54% in the
ESW group (p<0.05). Tacrolimus levels were on average 11.0 (95 % CI 10.6–11.5) in the
steroid group and 10.1 in the ESW group (95 % CI 9.7–10.5), p<0.05. There was no significant
difference in eGFR or rejection rates between the two groups.
Conclusions:
Although early RT biopsy rates have doubled since adopting an ESW protocol, AR rate has not
increased.