Outcomes Following Extracorporeal Photopheresis for Chronic Lung Allograft Dysfunction Following Lung Transplantation: A Single-Center Experience.

INTRODUCTION: Survival following lung transplantation (LTx) is limited by the development of chronic lung allograft dysfunction (CLAD), for which there are few effective therapies and no standardized management. Several small studies have demonstrated the effectiveness of extracorporeal photopheresis (ECP) as a therapeutic option for CLAD. METHODS: A retrospective descriptive audit of 12 LTx recipients who received rescue ECP for CLAD over 5 years (2013-2018) at the Alfred Hospital, Melbourne, Australia, was completed. Nonresponders to ECP were defined as patients who experienced a 20% decrease in forced expiratory volume (FEV1) within 6 weeks of commencing therapy. RESULTS: Mean time since LTx was 849 days and mean time since diagnosis of CLAD was 131 days. Fifty-eight percent of patients were male (n = 7) and 67% responded to ECP therapy (n = 8). Among responders, the mean (95% confidence interval) decline in FEV1 pre-ECP was 9.0 mL/day (5-12 mL/day), compared to 1.4 mL/day (0-4 mL/day) post-ECP (P = .01). Among nonresponders, mean (95% confidence interval) decline in FEV1 was 7.2 mL/day (4-10 mL/day) pre-ECP and 5.0 mL/day (3-7 mL/day) post ECP (P = .2). Nonresponders were more likely to be female (P = .01) and neutropenic (P = .005). Patients with prior exposure to anti-thymocyte globulin had a lowered response to ECP. CONCLUSION: Rescue ECP arrested the decline of lung function in 67% of patients with CLAD. Sex, pre-ECP neutrophil count, and exposure to anti-thymocyte globulin may help determine response to ECP. Future clinical trials are needed to confirm this effect, help predict response to therapy, and ultimately guide the placement of ECP in the treatment algorithm for CLAD. Copyright © 2020 Elsevier Inc. All rights reserved.
BACKGROUND:
There is no standard definition for “HLA incompatible” transplants. For the first time, we systematically assessed how HLA incompatibility was defined in contemporary peer-reviewed publications and its prognostic implication to transplant outcomes.
 
METHODS:
We combined 2 independent searches of MEDLINE, EMBASE, and the Cochrane Library from 2015 to 2019. Content-expert reviewers screened for original research on outcomes of HLA-incompatible transplants (defined as allele or molecular mismatch and solid-phase or cell-based assays). We ascertained the completeness of reporting on a predefined set of variables assessing HLA incompatibility, therapies, and outcomes. Given significant heterogeneity, we conducted narrative synthesis and assessed risk of bias in studies examining the association between death-censored graft failure and HLA incompatibility.
 
RESULTS:
Of 6656 screened articles, 163 evaluated transplant outcomes by HLA incompatibility. Most articles reported on cytotoxic/flow T-cell crossmatches (n = 98). Molecular genotypes were reported for selected loci at the allele-group level. Sixteen articles reported on epitope compatibility. Pretransplant donor-specific HLA antibodies were often considered (n = 143); yet there was heterogeneity in sample handling, assay procedure, and incomplete reporting on donor-specific HLA antibodies assignment. Induction (n = 129) and maintenance immunosuppression (n = 140) were frequently mentioned but less so rejection treatment (n = 72) and desensitization (n = 70). Studies assessing death-censored graft failure risk by HLA incompatibility were vulnerable to bias in the participant, predictor, and analysis domains.
 
CONCLUSIONS:
Optimization of transplant outcomes and personalized care depends on accurate HLA compatibility assessment. Reporting on a standard set of variables will help assess generalizability of research, allow knowledge synthesis, and facilitate international collaboration in clinical trials.