BK Virus in Simultaneous Pancreas Kidney Transplantation

UVA, P; LEON, L; MINUÉ, ELENA; DOTTA, A; TONIOLO, F; PILOTTI, R.; CHULUYAN, E.; CASADEI, D

Congreso; American Transplant Congress; 2017

BK virus (BKV) may produce nephropathy that could lead to graft failure. The most effective treatment is to decrease immunosuppression (IS). In simultaneous pancreas kidney (SPK) transplantation, however, this could lead to pancreas rejection. Therefore BKV treatment in SPK remains unclear.Materials and Methods: Since 2013 we have performed detection of BKV viremia at 3, 6 and 12 months in new transplants and yearly in older transplants. Patients with viremia had kidney and pancreas biopsies performed. Our standard IS protocol includes induction with steroids and depleting antibodies and maintenance with tacrolimus, mycophenolate and steroids.Results: 7 patients had asymptomatic BKV viremia. Biopsies showed 2 stage I, 3 stage II nephropathies and 2 patients without nephropathy. Tacrolimus levels were reduced, and mycophenolate was switched to leflunomide. Additionally 5 patients received 2g/kg of IVIG. Six patients had negative viremia in less than 6 months and remained negative until last visit. Two of them experience graft dysfunction and had biopsy proven rejection of the kidney (Banff 1A) at 9 months and of both organs (Banff 1 + 1A) at 7 months, treated with steroids and steroids and Thymoglobulin respectively. After rejection leflunomide was switched to everolimus. They all maintained stable creatinine except the patient with kidney rejection (Cr 2.3 from 1.7). Interestingly, of the two patients that didn´t receive IVIG one had rejection and the other continues to have viremia.In addition to these 7 asymptomatic patients, another 4 patients presented with kidney dysfunction and were found to have BKV nephropathy. 3 of them had a recent treatment of rejection and the other was only 3 months after induction therapy. These patients had the same treatment for BKV nephropathy described with 2 of them receiving IVIG. All had negative viremia at 6 months and after. 2 of them had a rejection episode of the pancreas (Banff 1) at 1 month and of both organs (Banff 1B and 1) at 26 months.Conclusion: BKV viremia has a high incidence of subclinical nephropathy. Switching mycophenolate to leflunomide with or without IVIG has good results in controlling viremia. Duration of this protocol is unclear as this could lead to either graft rejection. IVIG treatment may protect against rejection and restitution of original immunosuppression after controlling viremia might be an approach to avoid this.