Immunoadsorption for Treatment of Antibody Mediated Rejection after Lung Transplantation

PURPOSE: Antibody mediated rejection (AMR) has recently emerged as an important risk factor for lung allograft dysfunction and mortality. Several clinical protocols have been proposed to try to remove donor specific antibodies (DSA) and prevent their future development, including intravenous immunoglobulin (IVIG), therapeutic plasma exchange (TPE), rituximab and other. Unlike traditional TPE, immunoadsorption (IAS) is a blood-purification technique that enables the selective removal of immunoglobulins from separated plasma through high-affinity adsorbers; advantageously, IAS does not remove other plasma components such as fibrinogen and compounds of the coagulation cascade, reducing potential adverse effects. Our centre implemented a multimodality strategy including steroids, immunoadsorbption, IVIG and Rituximab. METHODS: All adult lung transplant (LuTx) recipients receiving a diagnosis of AMR (based on 2016 ISHLT consensus definition), were considered eligible to receive this treatment: pulsed methylprednisolone (10 mg/Kg), 5 cycles of IAS, IVIG (2 g/Kg) and rituximab (375 mg/m^2). Of note, C4d staining is not currently available at our institution. RESULTS: Between 2016 and 2018, four patients received multimodality antibody directed therapy for AMR after LuTx. Details can be found in table 1. 2 out of the 4 patients qualified for chronic lung allograft dysfunction (CLAD) prior to protocol start (patient 1 and 3). No adverse events were registered during IAS procedures, but patient 3 suffered transfusion related acute lung injury while receiving IVIG. However, patient 3's death was attributed to progressive allograft failure and not to the therapy itself. CONCLUSION: Following this treatment, while the total number of the original DSA and the value of MFI of the originally observed DSA decreased, clinical outcomes were variable: 2 patients are experiencing long term clinical stability, but the others rapidly progressed to severe CLAD.