Living-donor Lobar Lung Transplantation Research Articles

Donor's long-term quality of life following living-donor lobar lung transplantation.

Living-donor lobar lung transplantation is an alternative procedure to deceased donation lung transplantation. It involves graft donation from healthy donors; however, only a few reports have discussed its long-term prognosis in living lung donors and their associated health-related quality of life. This study aimed to examine living lung donors' health-related quality of life. In our cross-sectional survey of living lung donors, we assessed health-related quality of life-based on three key aspects (physical, mental, and social health) using the 36-Item Short Form Health Survey. We also evaluated chronic postoperative pain and postoperative breathlessness using the numeric rating scale and the modified Medical Research Council Dyspnea scale, respectively. We obtained consent from 117 of 174 living lung donors. The average scores of the living lung donors on the 36-Item Short Form Health Survey were higher than the national average. However, some donors had poorer physical, mental, and social health, with lower summary scores than the national averages. Low mental component summary predictors included donor age (<40 years; odds ratio=10.2; p<.001) and recipient age (<18 years; odds ratio=2.73; p<.032). Low role-social component summary predictors included high lung allocation score (≥50; odds ratio=3.94, p<.002) and recipient death (odds ratio=3.64; p=.005). There were no predictors for a physical component summary. Additionally, many donors did not complain of pain or dyspnea. Living lung donors maintained an acceptable long-term health-related quality of life after surgery. Potential donors should be informed of relevant risk factors, and high-risk donors should receive appropriate support.

Comparison of living-donor lobar lung transplantation and cadaveric lung transplantation for pulmonary hypertension.

Living-donor lobar lung transplantation (LDLLT) is a life-saving procedure for critically ill patients with various lung diseases, including pulmonary hypertension (PH). However, there are concerns regarding the development of heart failure with pulmonary oedema after LDLLT in which only 1 or 2 lobes are implanted. This study aimed to compare the preoperative conditions and postoperative outcomes of LDLLT with those of cadaveric lung transplantation (CLT) in PH patients. Between 2008 and 2021, 34 lung transplants for PH, including 12 LDLLTs (5 single and 7 bilateral) and 22 bilateral CLTs, were performed. Preoperative variables and postoperative outcomes were retrospectively compared between the 2 procedures. Based on the preoperative variables of less ambulatory ability (41.7% vs 100%, P < 0.001), a higher proportion of World Health Organization class 4 (83.3% vs 18.2%, P < 0.001) and higher mean pulmonary artery pressure (74.4 vs 57.3 mmHg, P = 0.040), LDLLT patients were more debilitated than CLT patients. Nevertheless, hospital death was similar between the 2 groups (8.3% vs 9.1%, P > 0.99, respectively). Furthermore, the 5-year overall survival rate was similar between the 2 groups (90.0% vs 76.3%, P = 0.489). Although LDLLT patients with PH had worse preoperative conditions and received smaller grafts than CLT patients, LDLLT patients demonstrated similar perioperative outcomes and prognoses as CLT patients. LDLLT is a viable treatment option for patients with PH.

Outcome and growth of lobar graft after pediatric living-donor lobar lung transplantation

Living-donor lobar lung transplantation (LDLLT) remains a life-saving option for pediatric patients with respiratory failure. However, the long-term survival and post-transplant quality of adult lobar grafts transplanted into children are unknown. Therefore, this study aimed to evaluate the outcomes of pediatric LDLLT and post-transplant graft growth. We retrospectively reviewed the prospectively collected clinical data of 25 living-donor lung transplantations performed in 24 pediatric recipients aged ≤17 years. The annual pulmonary function test data and computed tomography scans of 12 recipients, followed up for >5 years without significant complications, were used to evaluate growth in height, graft function, and radiological changes. The Kaplan-Meier method and simple linear regression were performed for analysis. Bilateral lower lobe transplantation was performed in 12 patients, unilateral lower lobe transplantation in 12, and bilateral middle lobe transplantation in 1. The median volumetric size matching at transplantation was 142% (range, 54%-457%). The 5- and 10-year overall survival rates were 87.7% and 75.1༅, respectively. Chronic lung allograft dysfunction occurred in 2 patients. During a median follow-up of 6 years, the median increases in height and vital capacity were 14.4% (range, 0.80%-43.5%) and 58.5% (range, 6.7%-322%), respectively. Graft weight was positively correlated with graft volume (r2=0.622, p<0.001) after the graft volume exceeded the original lobar volume in the donor. This study shows that pediatric LDLLT offers satisfactory long-term survival, with the growth of mature adult lobes transplanted into growing children.

Living Donor Lobar Lung Transplant for a Patient With Lung Disease Caused by ABCA3 Gene Mutations: A Case Report

Recessive gene mutations in ABCA3 cause lethal neonatal respiratory distress, and pediatric and adult interstitial lung disease. The effectiveness of medical treatments is limited and a subset of such patients will eventually require lung transplantation. A 20 months old boy developed interstitial lung disease and was treated with hydroxychloroquine, which had a significant effect. Sequence analysis of ABCA3 gene revealed newly discovered compound heterozygous mutations. His respiratory dysfunction gradually progressed over years and he underwent living-donor lobar lung transplantation (LDLLT) at 8 years of age with his parents serving as bilateral lobar donors. The parents had been genetically examined beforehand and found to be carriers who had one allele with an ABCA3 gene mutation and the other with no mutation. The recipient has been well without chronic lung allograft dysfunction and his parents have been enjoying healthy social lives for 7 years since the operations. LDLLT appears to be a valid option for selected children with ABCA3 gene mutations who are too ill to wait for cadaveric lung transplantation. When relatives of the recipient with ABCA3 gene mutation are deemed potential donors for LDLLT, sequence analyses of the donors are indispensable to exclude the possibility that they are late-onset patients of this recessive hereditary disease.

Long-Term Persisting Donor-Derived Human Leukocyte Antigen Antibody as a Possible Passenger Lymphocyte Syndrome Following Lung Transplantation: A Case Report

Herein, we reported the transfer of donor-derived antihuman leukocyte antigen (HLA) antibodies in 2 recipients after lung transplantation. Case 1: A 39-year-old woman with pleuroparenchymal fibroelastosis underwent a single brain-dead donor lung transplantation. Antibody screening 36 days after transplantation demonstrated high levels of de novo nondonor HLA class I-specific antibodies. The antibody screening in the donor serum revealed that the donor demonstrated a largely overlapping antibody profile. Importantly, the donor serum also included high-level HLA-specific antibodies against the recipient HLA-specific antigens, which were not detected in the recipient sera after transplantation. Donor-derived anti-HLA antibodies were still detected in the recipient 39 months after transplantation, without causing any complications such as graft-vs-host disease. Case 2: A 47-year-old woman underwent living-donor lobar lung transplantation for pulmonary complications after bone marrow transplantation with a right lower lobe from her husband and the left lower lobe from her sister. On postoperative day 39, the recipient's anti-HLA-class I antibody profile was found to be similar to that of the highly sensitized left lung donor. These donor-derived anti-HLA antibodies remained to be produced in the recipient 66 months after transplantation, without the development of complications.

Assessment of listing criteria for lung transplant candidates with interstitial lung disease.

Lung transplantation (LT) is an effective treatment for patients with interstitial lung disease (ILD) refractory to medical treatment. Although the cases of cadaveric LT (CLT) have increased, the donor shortage in Japan has remained severe. This study aimed to evaluate the International Society of Heart and Lung Transplantation (ISHLT) listing criteria for LT in patients with ILD by predicting outcomes during the waiting time for CLT. We retrospectively identified 166 patients with fibrotic ILDs who were evaluated and registered for CLT at Kyoto Universal Hospital from April 1, 2008, to December 31, 2017. We examined the correlation between individual parameters of the ISHLT listing criteria and patient outcomes. Among 166 patients, 57 (34.3%) underwent CLT, whereas 83 (50.0%) died before CLT. The median survival time from the date of registration was 22.5months. The 2-year survival rate was 47.8%. On multivariate Cox proportional hazards analysis, relative decline of percent predicted forced vital capacity (%FVC) in 6months ≥ 10% (hazard ratio [HR]: 1.72; 95% confidence interval [95%CI]: 1.03-2.87, p = 0.04) and 6-min walking distance (6MWD) < 250m (HR: 2.77; 95%CI: 1.64-4.69, p < 0.001) were independently associated with worse outcome (i.e., death or living-donor lobar LT). The 2014 ISHLT criteria could appropriately identify patients with ILD who have a potentially poor prognosis. In particular, 6-month decline in %FVC and shorter 6min walk distance may be useful for selecting patients with higher risks of mortality.

Technical Aspects of Lung Transplantation: Pediatric and Lobar Transplantation.

Fewer patients undergo pediatric lung transplantation (PLT) than adult lung transplantation. Size mismatch is the key factor that limits the availability of potential donors. Every candidate for PLT is in a different scenario in terms of age, height and weight, size of structures, indications for PLT, the concomitant presence of a cardiac anomaly, and other individual-specific factors; thus, a thorough understanding of pediatric patients’ medical problems is essential. Living-donor lobar lung transplantation (LDLLT) has only been performed once in Korea to date. However, since each step in the LDLLT is a well-established procedure, including intrapericardial lobectomy, lung procurement, and lobar lung transplantation, qualified surgeons and lung transplantation teams are competent to perform LDLLT in clinically necessary situations.

Right-to-Left Inverted Living-Donor Lobar Lung Transplantation

In standard bilateral living-donor lobar lung transplantation (LDLLT), right and left lower lobes donated by 2 healthy donors are implanted into a recipient after right and left pneumonectomies. Because only 2 lobes are implanted, the grafts may be too small for an adult recipient. To overcome size mismatch, we have developed a technique of right-to-left inverted LDLLT based upon the fact that the right lower lobe is generally larger than the left lower lobe. In right-to-left inverted LDLLT, 2 donors donate their right lower lobes. The right graft is implanted in the right side of the recipient. The left graft is inverted and implanted in the left side. This operation is indicated when total graft forced vital capacity (FVC) is less than 60% of the recipient's predicted FVC or when donor's left lower lobectomy is technically difficult due to interlobar pulmonary artery anatomy. In standard bilateral living-donor lobar lung transplantation (LDLLT), right and left lower lobes donated by 2 healthy donors are implanted into a recipient after right and left pneumonectomies. Because only 2 lobes are implanted, the grafts may be too small for an adult recipient. To overcome size mismatch, we have developed a technique of right-to-left inverted LDLLT based upon the fact that the right lower lobe is generally larger than the left lower lobe. In right-to-left inverted LDLLT, 2 donors donate their right lower lobes. The right graft is implanted in the right side of the recipient. The left graft is inverted and implanted in the left side. This operation is indicated when total graft forced vital capacity (FVC) is less than 60% of the recipient's predicted FVC or when donor's left lower lobectomy is technically difficult due to interlobar pulmonary artery anatomy.

Long-Term Outcome and the Radiological Evaluation of Lung Growth After Living-Donor Lobar Lung Transplantation in Pediatric Patients

<h3>Purpose</h3> Living-donor lobar lung transplantation (LDLLT) is a valuable life-saving option for pediatric patients due to the scarcity of pediatric donor. The purpose of this study was to evaluate the long-term outcome and the lung growth of the transplanted adult lobe in growing pediatric recipients. <h3>Methods</h3> The clinical data of 30 pediatric LDLLTs (age<17) performed between June 2008 and December 2020 were reviewed. The annual pulmonary function test and CT scan data of the 12 recipients who were followed up for more than 5 years without significant complications were used for evaluating growth in height, graft function and radiological evidence of lung growth. Radiologic graft weight and air volume were calculated with CT value using 3D volume analyzer. <h3>Results</h3> Median age and height were 10 (3-15) and 125.3 cm (95-165), respectively. The procedures were unilateral transplantation of right lower lobe (n=12), bilateral transplantation of 2 lower lobes (n=13), and others including segmental and middle lobe transplantation (n=5). Ten-year overall survival and CLAD-free survival were 76.8% (Fig A) and 64.4%, respectively. In 12 recipients followed up for more than 5 years (median 6.5 years), the mean increase in height, vital capacity, and graft volume were 15.9%, 14.0%, and 55.4% (Fig B), respectively. Mean CT volumetric size matching (donor/recipient) at transplantation was 154% (53-367). The transplanted graft volume exceeded the original volume within the donor chest in 11 of 12 recipients (92%). During the median follow-up period of 3.0 years after the transplanted graft volume exceeded original one, the mean increase in radiologic graft weight was 6.6% and the radiologic graft weight was positively correlated with its air volume (r²=0.580, p<0.01, Fig C). <h3>Conclusion</h3> Pediatric LDLLT provided satisfactory long-term outcome with the radiological suggestion that the lung growth of transplanted mature lobe occurred in growing chest cavity.

Long-Term Persisting Donor-Derived Anti-Human Leukocyte Antigen (HLA) Antibody as a Possible Passenger Lymphocyte Syndrome Following Lung Transplantation

<h3>Introduction</h3> A routine screening for the presence of HLA-specific antibodies after solid organ transplantation, produced by recipient B cells or plasma cells, is important for the management of antibody-mediated rejection. A novel possibility has recently been suggested in a few clinical case reports, where some de novo HLA-specific antibodies could continue to be produced by donor passenger B lymphocytes/plasma cells. We herein report the transfer of donor-derived anti-HLA antibodies in two recipients following lung transplantation. <h3>Case Report</h3> Case 1: A 39‐year‐old woman with pleuroparenchymal fibroelastosis underwent single lung transplantation with a left lung from a brain-dead donor. Antibody screening 36 days after transplant showed high levels of de novo non-donor HLA class I-specific antibodies. Then antibody screening in the donor serum identified that the donor showed a largely overlapping antibody profile to that found in the recipient. Importantly, the donor serum also included high-level HLA-specific antibodies against the recipient HLA-specific antigens, which were not detected in the recipient sera after transplantation. The donor-derived anti-HLA antibodies have still been detected in the recipient at 39 months after transplantation, which have never caused any complications such as graft-versus-host disease (GVHD). Case 2: A 47‐year‐old woman underwent living donor lobar lung transplantation for pulmonary complications after bone marrow transplantation with the right lower lobe from her husband and the left lower lobe from her sister. On postoperative day 39, the recipient anti- HLA-class I antibody profile was found to be similar to that of the high-sensitized left lung donor. These donor-derived anti-HLA antibodies have remained to be produced in the recipient at 66 months after transplantation without development of complications such as GVHD. <h3>Summary</h3> This case report suggests that alloreactive passenger B cells or plasma cells located within the highly sensitized donor lungs could lead to the early production of de novo anti-HLA-specific antibodies in the lung transplant recipients. Although there have been no overt clinical manifestations in either of the patients so far, the clinical significance of transfer of donor HLA-specific allosensitization should be elucidated.

Cytomegalovirus Infection After Lung Transplantation

<h3>Purpose</h3> Cytomegalovirus (CMV) is one of the most important pathogens causing infections after lung transplantation (LTx), since it is known to have influences on postoperative outcomes after LTx and occurrence of chronic lung allograft dysfunction (CLAD). In this study, we retrospectively reviewed the frequency and managements of CMV infection after LTx. <h3>Methods</h3> This study included 227 lung transplants (92 living-donor lobar lung transplants [LDLLTs] and 135 deceased-donor lung transplants [DDLTs]) performed between 2008 and 2019. In our institution, we usually give antivirus prophylaxis until 1 year after LTx with oral administration of valganciclovir (VGCV). <h3>Results</h3> CMV infection after LTx occurred in 64 recipients (28.2%), and the median duration between LTx and CMV infection was 215 days (range: 6-2566 days). Among these 64 recipients, 18 recipients (28.1%) were CMV-mismatched (donor + /recipient -). CMV viremia was observed in 50 recipients, while end-organ CMV disease occurred in 14 recipients. Among 55 recipients having CMV infection after the completion or discontinuation of antivirus prophylaxis with VGCV, the median time from the end of prophylaxis to CMV infection was 3 months (range: 1-83 months). As treatments for CMV infection, the administration of ganciclovir (GCV) was mainly performed in most cases. Foscarnet was used for 5 recipients due to the myelosuppression (n = 2) and the suspicion of GCV resistance (n = 3). Both overall survival (OS) and CLAD-free survival of recipients having CMV infection were significantly worse than those of recipients not having CMV infection both in LDLLT (p = 0.013 [OS] and p = 0.035 [CLAD-free survival], Figure A and B) and in DDLT (p<0.001 [OS] and p = 0.003 [CLAD-free survival], Figure C and D). <h3>Conclusion</h3> The frequency of CMV infection after LTx was relatively high, and many CMV infections occurred early after the completion or discontinuation of VGCV administration. The prognoses of LTx recipients having CMV infection were worse than those not having CMV infection both in LDLLT and in DDLT.

Outcome and Growth of Lobar Graft After Pediatric Living-Donor Lobar Lung Transplantation: A Retrospective Cohort Study

Outcome and Growth of Lobar Graft After Pediatric Living-Donor Lobar Lung Transplantation: A Retrospective Cohort Study

Long-term outcomes of living-donor lobar lung transplantation

ObjectiveAlthough living-donor lobar lung transplantation (LDLLT) enables an intermediate survival similar to cadaveric lung transplantation, the long-term outcome remains unknown. We examined the long-term outcomes of 30 patients who received LDLLT more than 16 years previously. MethodsWe retrospectively reviewed the clinical data of 30 patients who underwent LDLLT (bilateral LDLLT, 29 patients; single LDLLT, 1 pediatric patient) between October 1998 and April 2004. ResultsLDLLT was performed for 25 female and 5 male patients ranging in age from 8 to 55 years. The diagnoses included pulmonary hypertension (n = 11), pulmonary fibrosis (n = 7), bronchiolitis obliterans (n = 5), and others (n = 7). At a median follow-up of 205 months, 22 patients were alive and 8 were dead. The causes of death were infection (n = 3), malignancy (n = 2), acute rejection (n = 2), and chronic lung allograft dysfunction (CLAD; n = 1). Unilateral CLAD occurred in 17 patients (56.7%), but only 1 of these patients subsequently developed bilateral CLAD. Two patients underwent bilateral cadaveric lung retransplantations. The 5-, 10-, and 15-year CLAD-free survival rates were 80.0%, 62.8%, and 44.3%, respectively. Malignancy occurred in 7 patients. Two of 5 patients with chronic kidney disease requiring hemodialysis underwent living-donor kidney transplantation. The 5-, 10-, and 15-year overall survival rates were 96.7%, 86.7%, and 73.3%, respectively. ConclusionsAlthough only 2 lobes are implanted, LDLLT provides encouraging long-term outcomes. In patients with unilateral CLAD, the functioning contralateral graft might contribute to a favorable long-term outcome.

Living-donor lobar lung transplantation.

Living-donor lobar lung transplantation (LDLLT) has become an important life-saving option for patients with severe respiratory disorders, since it was developed by a group in the University of Southern California in 1993 and introduced in Japan in 1998 in order to address the current severe shortage of brain-dead donor organs. Although LDLLT candidates were basically limited to critically ill patients who would require hospitalization, the long-term use of steroids, and/or mechanical respiratory support prior to transplantation, LDLLT provided good post-transplant outcomes, comparable to brain-dead donor lung transplantation in the early and late phases. In Kyoto University, the 5- and 10-year survival rates after LDLLT were reported to be 79.0% and 64.6%, respectively. LDLLT should be performed under appropriate circumstances, considering the inherent risk to the living donor. In our transplant program, all living donors returned to their previous social lives without any major complications, and living-donor surgery was associated with a morbidity rate of <15%. Both functional and anatomical size matching were preoperatively performed between the living-donor lobar grafts and recipients. Precise size matching before surgery could provide a favorable pulmonary function and exercise capacity after LDLLT. Various transplant procedures have recently been developed in LDLLT in order to deal with the issue of graft size mismatching in recipients, and favorable post-transplant outcomes have been observed. Native upper lobe-sparing and/or right-to-left inverted transplantation have been performed for undersized grafts, while single-lobe transplantation has been employed with or without contralateral pneumonectomy and/or delayed chest closure for oversized grafts.

Impacts of single nucleotide polymorphisms in Fc gamma receptor IIA ( rs1801274 ) on lung transplant outcomes among Japanese lung transplant recipients

This study aimed to analyze the influences of single nucleotide polymorphisms (SNPs) in Fc gamma receptor IIA (FCGR2A) on postoperative outcomes after lung transplantation (LTx). We enrolled 191 lung transplant recipients [80 undergoing living-donor lobar lung transplants (LDLLTs) and 111 undergoing deceased-donor lung transplants (DDLTs)] in this study. We identified SNPs in FCGR2A (131 histidine [H] or arginine [R]; rs1801274) and reviewed the infectious complication-free survival after ICU discharge. The SNPs in FCGR2A comprised H/H (n = 53), H/R (n = 24), and R/R (n = 3) in LDLLT and H/H (n = 67), H/R (n = 42), and R/R (n = 2) in DDLT. Recipients with H/H (H/H group) and those with H/R or R/R (R group) were compared in the analyses of infectious complications. In multivariate analyses, the R group of SNPs in FCGR2A was associated with pneumonia-free survival {HR: 2.52 [95% confidence interval (CI): 1.35-4.71], P = 0.004}, fungal infection-free survival [HR: 2.50 (95% CI: 1.07-5.84), P = 0.035], and cytomegalovirus infection-free survival [HR: 2.24 (95% CI: 1.07-4.69), P = 0.032] in LDLLT, but it was not associated with infectious complication-free survival in DDLT. Therefore, in LDLLT, more attention to infectious complications might need to be paid for LTx recipients with H/R or R/R than for those with H/H.

Emphysematous changes and lower levels of plasma irisin are associated with bronchiolitis obliterans syndrome after bilateral living-donor lobar lung transplantation.

Decreased irisin levels may be associated with the development of emphysema. Similarly, emphysematous changes may develop in patients with chronic lung allograft dysfunction (CLAD) after living-donor lobar lung transplantation (LDLLT). We investigated the severity of emphysematous changes and the relationship between irisin levels and CLAD after bilateral LDLLT and cadaveric lung transplantation (CLT). The subjects of this retrospective study were 59 recipients of bilateral LDLLT (n = 31) or CLT (n = 28), divided into a non-CLAD group (n = 41), a LDLLT-CLAD group (n = 11), and a CLT-CLAD group (n = 7). We compared the severity of emphysematous changes, the skeletal muscle mass, and the plasma irisin levels among the groups. The emphysematous changes were significantly more severe in the LDLLT-CLAD and CLT-CLAD groups (p = 0.046 and 0.036), especially in patients with bronchiolitis obliterans syndrome (BOS), than in the non-CLAD group. Although the skeletal muscle mass was similar in all the groups, the plasma irisin levels were significantly lower in the LDLLT-CLAD group (p = 0.022), especially in the patients with BOS after LDLLT, than in the non-CLAD group. Emphysematous changes and lower levels of plasma irisin were associated with CLAD, especially in patients with BOS, after bilateral LDLLT.

Various techniques for anastomosis of pulmonary arteries with size mismatch during lung transplantation.

Various techniques for anastomosis of pulmonary arteries with size mismatch during lung transplantation.

“Hybrid Lung Transplantation” Combining Living Donor and Cadaveric Lung Transplants: Report of 2 Cases

We present 2 cases of "hybrid lung transplant," which included sequentially implanting a living lobar graft to 1 side and a cadaveric graft to the other side. This procedure was approved by the institutional review board at Okayama University Hospital. The 2 recipients were diagnosed with severe idiopathic pulmonary fibrosis, and living donor lobar lung transplant was considered; however, 2 appropriate donors were not available. Therefore, we accepted extended criteria donor lungs with a partial pressure of oxygen/fraction of inspired oxygen ratio of <251 mm Hg. However, 1 of the 2 patients developed grade 2 primary graft dysfunction. The living donor lobar lung had a low volume but was in good condition, which contributed to the patient's recovery after primary graft dysfunction during the perioperative period. The other patient's status of bronchiolitis obliterans syndrome had gradually progressed to grade 3, and only the living donor lung was functioning at that time. However, both patients are alive 5.5 and 4.2 years after lung transplant, respectively. Hybrid lung transplantation may increase patients' chances of receiving transplants because patients are not likely to survive while waiting for ideal donor lungs to become available.

Risk Assessment of Chronic Lung Allograft Dysfunction Phenotypes after Living-Donor Lobar Lung Transplantation According to the 2019 ISHLT Classification System

<h3>Purpose</h3> Chronic lung allograft dysfunction (CLAD) is known as one of the major fatal disorders in the long-term phase after lung transplantation. Because CLAD is a heterogeneous disease, proper classification of phenotypes is important to understand each pathogenesis. In this study, we retrospectively evaluated the impact of new 2019 ISHLT classification system on living-donor lobar lung transplantation (LDLLT). <h3>Methods</h3> Between 1998 and 2019, a total of 96 patients underwent LDLLT at our hospital, and 73 patients who underwent bilateral LDLLT were included in this study. CLAD after bilateral LDLLT were diagnosed and classified according to the ISHLT consensus report in 2019. <h3>Results</h3> The median follow-up time was 10.3 years. A total of 27 (37.0%) patients were diagnosed as CLAD, including bronchiolitis obliterans syndrome (BOS) (n = 8, 29.6%), restrictive allograft syndrome (RAS) (n = 11, 40.7%), mixed (n = 1, 3.7%), undefined (n = 2, 7.4%), and unclassified (n = 5, 18.5%). CLAD developed in the unilateral lung in 26 patients. Five-year survival of the patients developing CLAD after LDLLT was 84.1%, whereas 5-year survival of the patients after CLAD onset was 58.4%. Survival after CLAD onset was worse in the patients with RAS (p=0.008) and undefined (p=0.003) than those with BOS. Though survival after CLAD onset did not differ between the patients with or without CT opacities (p=0.40), the patients with restriction on pulmonary function test had significantly worse survival than those without restriction (Figure, p=0.001). <h3>Conclusion</h3> While the patients with BOS had better prognosis, the presence of restriction on pulmonary function test could predict worse prognosis of the CLAD patients after bilateral LDLLT.

Antibody Mediated Rejection of Unrelated Donor Lung

Introduction Living-donor lobar lung transplantation (LDLLT) arose from the need to transplant patients deemed unlikely to survive the waitlist for a deceased organ donor. Since the initiation of the lung allocation score (LAS), the wait time for cadaveric organs has significantly decreased in the USA as has the need for LDLLT. According to the Organ Procurement and Transplantation Network (OPTN), there have been 253 recipients of LDLLT in the USA. Of these, 95 were children and only 20 of them had a biologically unrelated donor. We present a case of graft dysfunction in a 28-year-old man who underwent bilateral LDLLT at age 9 for pulmonary arterial hypertension. He received a right lower lobe from his mother and a left lower lobe from a family friend. Case Report The patient presented with new onset dyspnea, productive cough, and hypoxemia. He had a significant decline in lung function, new left lung consolidation, and required hospitalization for hypoxemic respiratory failure. Work-up was significant for undetectable immunosuppressant levels and a new DPB1 antibody. Bilateral transbronchial biopsies were negative for acute cellular rejection, however BAL cell count showed significant lymphocytosis and eosinophilia. He was treated with pulse dose IV steroids followed by plasmapheresis, IVIG, and Rituximab. Oxygen requirement decreased and he was discharged home. A lung ventilation-perfusion scan performed a few months later showed marked asymmetric reduction in perfusion to the left lung. Despite persistent volume loss in the left allograft and decreased lung function, he has remained clinically stable on monthly IVIG infusions and is now off supplemental oxygen. Donor HLA typing was not available to us as the transplant occurred in 2001 when DPs were not routinely typed. However, considering the overall presentation and the patient's response to therapy, we presume the DPB1 is a donor specific antibody (DSA). Summary Unilateral chronic lung allograft dysfunction (CLAD) has been described in bilateral LDLLT. The significance of HLA in the immune response of lung transplant recipients has gained recognition in recent years. Data suggest that the development of alloantibodies as a consequence of HLA mismatching has been shown to correlate with development of CLAD. This case illustrated a unique presentation of presumed antibody mediated rejection of unrelated donor lung in the setting of subtherapeutic immunosuppression.