Abstract: SA-PO526

Evolution of Post-Transplant Atypical Hemolytic Uremic Syndrome (aHUS)

Session Information

Category: Transplantation

  • 1702 Transplantation: Clinical and Translational

Authors

  • Miranda, Silvana Maria Carvalho, Hospital Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
  • Souza, Pedro Augusto Macedo, None, Belo Horizonte, MINAS GERAIS, Brazil
  • Pereira jr, Gerson Marques, Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
  • Felipe, Carlos rafael Almeida, Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
  • Souza, Vanessa Brandão, Hospital Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
  • Piana, Izabela Lara, None, Belo Horizonte, MINAS GERAIS, Brazil
  • Alvarenga, Andre Sousa, Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
  • Ribeiro, Cláudia, Hospital Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
Background

The incidence of post-transplant thrombotic microangiopathy (PT-TMA) ranges from 1-5% and causes reduction of graft survival. Nevertheless, diagnosis of aHUS is difficult due to multiple potential triggers. Timely treatment of aHUS with eculizumab may improve prognosis.

Methods

Retrospective cohort review of 306 kidney transplant recipients (KTR) from September 2012 to September 2016 at a single brazilian center. PT-TMA was diagnosed by graft biopsy or thrombotic microangiopathic syndrome.

Results

The incidence of PT-TMA was 3.9% (n = 12). Of these, two were diagnosed with acute antibody-mediated rejection, one tacrolimus induced and nine with aHUS by excluding secundary causes. The etiology of renal disease was unknown in six patients of aHUS group. The other three cases were attributed to diabetic nephropathy, malignant arterial hypertension and membranous nephropathy. Fifty five percent of aHUS patients received prednisone, tacrolimus (TAC) and mycophenolate while the remaining received prednisone, tacrolimus and everolimus. Six had TAC trough levels greater than 10 ng/mL, two greater than 20 ng/ml and none had everolimus trough levels greater than 6 ng/mL. All nine patients received eculizumab, two of which received plasmapheresis with no response. Median time from transplant to aHUS diagnosis was 81 (35.5 – 134.5) days. Median time from diagnosis to eculizumab treatment was 17 (4.5 – 134) days and was not different between those whose grafts survived or not. After eculizumab creatinine improved in five patients, three remain on dialysis and one suffered sudden death after two doses. Two of those who improved renal function, died, one from gastrointestinal bleeding and one from sepsis of cutaneous infection. Death censored graft survival was 55.6% in six months versus 83.5% in those who did not have aHUS. No graft failed after 6 months in aHUS group.

Conclusion

aHUS occurred until 6 months PT-TMA and was related to tacrolimus trough levels above 10 ng/mL in 66% of patients. aHUS has a great impact in graft survival leading to very poor prognosis. Time from diagnosis to treatment with eculizumab did not correlate to better graft survival, but the small sample size should be considered when interpreting these results.