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Abstract: SA-PO1060

Torque Teno Virus Load to Monitor Changes in Immunosuppression in Kidney Transplant Recipients with Indication Biopsy

Session Information

Category: Transplantation

  • 2102 Transplantation: Clinical

Authors

  • Reineke, Marvin, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Speer, Claudius, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Klein, Julian, Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Heidelberg, Germany, Heidelberg, Germany
  • Nusshag, Christian, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Kälble, Florian, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Mahler, Christoph Friedrich, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Zeier, Martin G., Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Bartenschlager, Ralf, Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Heidelberg, Germany, Heidelberg, Germany
  • Schnitzler, Paul, Heidelberg University, Medical Faculty Heidelberg, Department of Infectious Diseases, Virology, Heidelberg, Germany, Heidelberg, Germany
  • Morath, Christian, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
  • Benning, Louise, Department of Nephrology, University Hospital Heidelberg, Heidelberg, Germany, Heidelberg, Germany
Background

Torque teno virus (TTV) is a potential surrogate parameter to monitor immunocompetence in kidney transplant recipients (KTR) early after transplantation. However, its use in monitoring changes in immunosuppression in KTR late after transplantation with different graft-associated pathologies requires further investigation.

Methods

In this post-hoc analysis we quantified TTV load in sera of 108 KTR with indication biopsy. TTV loads of 34 KTR with biopsy-proven acute rejection (BPAR) and 74 KTR with other pathologies, including 15 KTR with BKV-associated nephropathy (BKVAN), were quantified the day of biopsy, as well as 7, 30 and 90 days post-biopsy to identify changes in viral load related to adjustments in immunosuppressive therapy.

Results

In KTR with no BPAR or BKVAN, TTV load increased in the first month following transplantation and was highest in patients that received a graft biopsy between 1-12 months post-transplantation. Subsequently, with a reduction in immunosuppression, there is a gradual decline in TTV load across patients (Figure 1A). Patients with BKVAN had significantly higher TTV loads than patients with BPAR or other pathology (P<0.001 for both; Figure 1B). When converted from mycophenolic acid (MPA) to mTOR-inhibitors because of BKVAN, TTV loads decreased significantly in these patients (P<0.01, Figure 1C). In KTR with BPAR who received high-dose corticosteroid pulse therapy, a significant increase in TTV loads was observed between biopsy to 30d and 90d post-biopsy (P<0.05 and P<0.01, respectively; Figure 1D).

Conclusion

TTV load reflects changes in immunosuppressive therapy. Individual changes of TTV load appear to be of greater significance than universally defined cut-off values as TTV load varies depending on the time after transplantation.