Published online Sep 10, 2018. doi: 10.5500/wjt.v8.i5.178
Peer-review started: May 3, 2018
First decision: May 22, 2018
Revised: June 14, 2018
Accepted: June 28, 2018
Article in press: June 28, 2018
Published online: September 10, 2018
To evaluate the role of a therapeutic regimen with plasma exchange, intravenous immunoglobulins and rituximab in chronic-active antibody-mediated rejection (cAMR) settings.
We compared 21 kidney transplant recipients (KTRs) with a diagnosis of cAMR in a retrospective case-control analysis: nine KTRs treated with plasmapheresis, intravenous immunoglobulins and rituximab (PE-IVIG-RTX group) vs 12 patients (control group) not treated with antibody-targeted therapies. We examined kidney survival and functional outcomes 24 mo after diagnosis. Histological features and donor-specific antibody (DSA) characteristics (MFI and C1q-fixing ability) were also investigated.
No difference in graft survival between the two groups was noted: three out of nine patients in the PE-IVIG-RTX group (33.3%) and 4/12 in the control group (33.3%) experienced loss of allograft function at a median time after diagnosis of 14 mo (min 12-max 18) and 15 mo (min 7-max 22), respectively. Kidney functional tests and proteinuria 24 mo after cAMR diagnosis were also similar in both groups. Only microvascular inflammation (glomerulitis + peritubular capillaritis score) was significantly reduced after PE-IVIG-RTX in seven out of eight patients (87.5%) in the PE-IVIG-RTX group (median score 3 in pre-treatment biopsy vs 1.5 in post-treatment biopsy; P = 0.047), without any impact on kidney survival and/or DSA characteristics. No functional or histological parameter at diagnosis was predictive of clinical outcome.
Our data showed no difference in the two year post-treatment outcome of kidney grafts treated with PE-IVIG-RTX for cAMR diagnosis, however there were notable improvements in microvascular inflammation in post-therapy protocol biopsies. Further studies, especially involving innovative therapeutic approaches, are required to improve the management and long-term results of this severe condition.
Core tip: Chronic-active antibody-mediated rejection (cAMR) is one of the major causes of poor long-term outcome in kidney transplantation, with no effective treatments currently available. We retrospectively compared 21 kidney transplant recipients with a diagnosis of cAMR, nine treated with plasmapheresis, intravenous immunoglobulins and rituximab vs 12 patients not treated with antibody-targeted therapies. Our data showed improvement in microvascular inflammation in post-therapy protocol biopsies without differences in functional outcomes at 24 mo, suggesting the lack of a prompt and marked effect of this therapeutic protocol. Further studies are required to improve the management and long-term results of this severe condition.