Therapeutics and Clinical Risk Management (Oct 2020)
Clinical Efficacy of Intravenous Immunoglobulin for BK Polyomavirus-Associated Nephropathy After Living Kidney Transplantation
Abstract
Soichi Matsumura,1 Taigo Kato,1,2 Ayumu Taniguchi,1 Masataka Kawamura,1 Shigeaki Nakazawa,1 Tomoko Namba-Hamano,3 Toyofumi Abe,1 Norio Nonomura,1 Ryoichi Imamura1 1Department of Urology, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan; 2Department of Urological Immuno-Oncology, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan; 3Department of Nephrology, Osaka University Graduate School of Medicine, Osaka 565-0871, JapanCorrespondence: Taigo KatoDepartment of Urology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, JapanTel +81-6-6879-3531Fax +81-6-6879-3534Email [email protected]: BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) is one of the most difficult infections to be treated after kidney transplantation. Although patients with BKPyVAN usually received a reduction of immunosuppressive agents, the majority of these patients undergo the loss of the graft kidney without any effective treatment afterward. Therefore, development of more effective therapy for BKPyVAN is eagerly expected.Patients and Methods: Among patients who underwent a kidney transplantation between January 2016 and April 2019 at our hospital, there were five cases of BKPyVAN. After the initial diagnosis, all patients discontinued administration of mycophenolate mofetil (MMF), which was not enough to diminish decoy cells in urine cytology test. Therefore, all patients received additional intravenous immunoglobulin (IVIG) (100 mg/kg/day) therapy for five days and were evaluated for the therapeutic effect of IVIG with immunohistochemical examination using re-biopsy samples of the graft kidney.Results: After IVIG therapy, 2 cases showed negative decoy cells in urine and 3 cases showed a drastic decrease of plasma BK virus load. Importantly, simian virus (SV) 40 large T antigens diminished after IVIG administration in all cases, which degraded polyomavirus nephropathy classification.Conclusion: Although it is difficult to treat BKPyVAN after kidney transplant, IVIG therapy was considered to a promising treatment to improve severity of BKPyVAN especially in cases that dose reduction of immunosuppressive agents was ineffective.Keywords: BK virus, BK virus nephropathy, intravenous immunoglobulin; IVIG, kidney transplantation, polyomavirus nephropathy classification
