Lung and heart-lung transplantation in patients with end-stage cystic fibrosis: the Stanford experience

Simultaneous combined transplantation: Intricacies in immunosuppression management

Simultaneous combined transplantation (SCT), i.e. the transplantation of two solid organs within the same procedure, can be required when the patients develop more than one end-stage organ failure. The development of SCT over the last 20 years could only be possible thanks to progress in the surgical techniques and in the perioperative management of patients in an ageing population. Performing such major transplant surgeries from the same donor, in a short amount of time, and in critical pathophysiological conditions, is often considered to be counterbalanced by the immune benefits expected from these interventions. However, SCT includes a wide array of different transplant combinations, with each time a different immunological constellation. Recent research offers new insights into the immune mechanisms involved in these different settings. Progress in the understanding of these immunological intricacies help to address the optimal induction and maintenance immunosuppressive treatment strategies. In this review, we summarize the different immunological benefits according to the type of SCT performed. We also incorporate the main outcomes according to the immunological risk at transplantation, and the deleterious impact of preformed or de novo donor-specific antibodies (DSA) in the different types of SCT. Finally, we propose comprehensive and evidence-based induction and maintenance immunosuppression strategies guided by the type of SCT.

Double-lung versus heart-lung transplantation for end-stage cardiopulmonary disease: a systematic review and meta-analysis

We compared posttransplant outcomes following double-lung transplantation (DLTx) and heart-lung transplantation (HLTx), based on a search of PubMed, Cochrane Library, and Embase, from inception to March 8, 2022, for studies that report outcomes of these procedures. We then performed a meta-analysis of baseline characteristics and posttransplant outcomes. Subgroup analyses were implemented according to indication, publication year, and center. This study was registered on PROSPERO (number CRD42020223493). Ten studies were included in this meta-analysis, involving 1230 DLTx patients and 1022 HLTx patients. The DLTx group was characterized by older donors (P = 0.04) and a longer allograft ischemia time (P < 0.001) than the HLTx group. The two groups had comparable 1-year, 3-year, 5-year, 10-year survival rates (all P > 0.05), with similar results identified in subgroup analyses. We found no significant differences in 1-year, 5-year, and 10-year chronic lung allograft dysfunction (CLAD)-free survival, length of intensive care unit stay and hospital stay, length of postoperative ventilation, in-hospital mortality, or surgical complications between the groups (all P > 0.05). Thus, DLTx provides similar posttransplant survival to HLTx for end-stage cardiopulmonary disease. These two procedures have a comparable risk of CLAD and other posttransplant outcomes.

Immunosuppression considerations in simultaneous organ transplant

Solid organ transplantation is a life-saving procedure for patients in the end stage of heart, lung, kidney, and liver failure. For patients with more than one failing organ, simultaneous organ transplantation has emerged as a viable treatment option. Immunosuppression strategies and outcomes for simultaneous organ transplant recipients have been reported, but often involve limited populations. Transplanting dual organs poses challenges in terms of balancing immunosuppression with immunologic risk and allograft damage from surgical complications. Furthermore, transplanting certain organs can impose considerations on the management of immunosuppression. For example, liver allografts may confer immunologic privilege and lower rates of rejection of other allografts. This review article evaluates immunosuppression strategies for simultaneous kidney-pancreas, liver-kidney, heart-kidney, heart-liver, heart-lung, lung-liver, and lung-kidney transplants. To date, no comprehensive review exists to address immunosuppressive strategies in simultaneous organ transplant populations. Our review summarizes the available literature and provides evidence-based recommendations regarding immunosuppression strategies in simultaneous organ transplant recipients.

Effects of Cyclosporine on Reperfusion Injury in Patients: A Meta-Analysis of Randomized Controlled Trials

Mitochondrial permeability transition pore (mPTP) opening due to its role in regulating ROS generation contributes to cardiac reperfusion injury. In animals, cyclosporine (cyclosporine A, CsA), an inhibitor of mPTP, has been found to prevent reperfusion injury following acute myocardial infarction. However, the effects of CsA in reperfusion injury in clinical patients are not elucidated. We performed a meta-analysis using published clinical studies and electronic databases. Relevant data were extracted using standardized algorithms and additional data were obtained directly from investigators as indicated. Five randomized controlled blind trials were included in our meta-analysis. The clinical outcomes including infarct size (SMD: −0.41; 95% CI: −0.81, 0.01; P = 0.058), left ventricular ejection fraction (LVEF) (SMD: 0.20; 95% CI: −0.02, 0.42; P = 0.079), troponin I (TnI) (SMD: −0.21; 95% CI: −0.49, 0.07; P = 0.149), creatine kinase (CK) (SMD: −0.32; 95% CI: −0.98, 0.35; P = 0.352), and creatine kinase-MB isoenzyme (CK-MB) (SMD: −0.06; 95% CI: −0.35, 0.23; P = 0.689) suggested that there is no significant difference on cardiac function and injury with or without CsA treatment. Our results indicated that, unlike the positive effects of CsA in animal models, CsA administration may not protect heart from reperfusion injury in clinical patients with myocardial infarction.

Lung transplantation for cystic fibrosis: results, indications, complications, and controversies

Survival in patients with cystic fibrosis (CF) has improved dramatically over the past 30 to 40 years, with mean survival now approximately 40 years. Nonetheless, progressive respiratory insufficiency remains the major cause of mortality in CF patients, and lung transplantation (LT) is eventually required. Timing of listing for LT is critical, because up to 25 to 41% of CF patients have died while awaiting LT. Globally, approximately 16.4% of lung transplants are performed in adults with CF. Survival rates for LT recipients with CF are superior to other indications, yet LT is associated with substantial morbidity and mortality (∼50% at 5-year survival rates). Myriad complications of LT include allograft failure (acute or chronic), opportunistic infections, and complications of chronic immunosuppressive medications (including malignancy). Determining which patients are candidates for LT is difficult, and survival benefit remains uncertain. In this review, we discuss when LT should be considered, criteria for identifying candidates, contraindications to LT, results post-LT, and specific complications that may be associated with LT. Infectious complications that may complicate CF (particularly Burkholderia cepacia spp., opportunistic fungi, and nontuberculous mycobacteria) are discussed.

Long-term successful outcomes from kidney transplantation after lung and heart-lung transplantation

BACKGROUND

Renal dysfunction is common after lung and heart-lung transplantation (Tx), and it limits the recipient's survival and quality of life. This study analyzed the outcomes of simultaneous and late kidney Tx following lung and heart-lung Tx.

METHODS

From a single-center retrospective chart review of 1031 lung and heart-lung Tx recipients, we identified 13 simultaneous or late kidney Tx cases in 12 patients.

RESULTS

Three patients underwent simultaneous deceased donor lung and kidney Tx. Eight patients underwent lung and heart-lung Tx, followed by nine living donor kidney Tx (including one ABO-incompatible Tx). One additional patient underwent a late deceased donor kidney Tx following heart-lung Tx. The median time from lung and heart-lung Tx to later kidney Tx was 127 (interquartile range [IQR], 23 to 263) months. Three patients died, 1 of sepsis, 1 of multiple organ failure, and 1 of transplant coronary disease. At a median follow-up of 33 (IQR, 10 to 51) months, 9 patients are alive and well. Eight patients required dialysis before kidney Tx for a median time of 14 months (IQR, 5 to 49). Kidney graft loss occurred in 1 patient at 51 months. After kidney Tx, dialysis was necessary in association with acute allograft dysfunction in 2 patients. No acute kidney rejection has been detected in any patient. Treatable acute lung rejection was seen in 1 patient. Well-preserved pulmonary function was noted in recipients of late kidney Tx.

CONCLUSIONS

Simultaneous kidney Tx and late deceased donor kidney Tx have challenges in the setting of lung Tx. By contrast, late living related kidney Tx after lung Tx is associated with excellent long-term survival and acceptable kidney and lung allograft function.

Liver transplant tolerance and its application to the clinic: can we exploit the high dose effect?

The tolerogenic properties of the liver have long been recognised, especially in regard to transplantation. Spontaneous acceptance of liver grafts occurs in a number of experimental models and also in a proportion of clinical transplant recipients. Liver graft acceptance results from donor antigen-specific tolerance, demonstrated by the extension of tolerance to other grafts of donor origin. A number of factors have been proposed to be involved in liver transplant tolerance induction, including the release of soluble major histocompatibility (MHC) molecules from the liver, its complement of immunosuppressive donor leucocytes, and the ability of hepatocytes to directly interact with and destroy antigen-specific T cells. The large tissue mass of the liver has also been suggested to act as a cytokine sink, with the potential to exhaust the immune response. In this review, we outline the growing body of evidence, from experimental models and clinical transplantation, which supports a role for large tissue mass and high antigen dose in the induction of tolerance. We also discuss a novel gene therapy approach to exploit this dose effect and induce antigen-specific tolerance robust enough to overcome a primed T cell memory response.

Effects of Sinus Surgery on lung Transplantation Outcomes in Cystic Fibrosis

Background

In cystic fibrosis (CF) patients who are candidates for lung transplant, pretransplant sinus surgery has been advocated to avoid bacterial seeding of the transplanted lungs. This study reviews the 17-year experience of pretransplant sinus surgery among CF patients at a major transplant center.

Methods

Retrospective chart review was performed in all CF patients who underwent heart-lung or lung transplantation at Stanford Medical Center between 1988 and 2005. Postoperative culture data from bronchoalveolar lavage (BAL) and sinus aspirates were evaluated, in addition to survival data.

Results

Eighty-seven CF transplant recipients underwent pretransplant sinus surgery; 87% (n = 59/68) of patients showed recolonization of the lung grafts with Pseudomonas on BAL cultures. The median postoperative time to recolonization was 19 days. Bacterial floras cultured from sinuses were similar in type and prevalence as the floras cultured from BAL. When compared with published series of comparable cohorts in which pretransplant sinus surgery was not performed, there was no statistically significant difference in the prevalence of Pseudomonas recolonization. Times to recolonization also were similar. Survival rates in our cohort were similar to national survival rates for CF lung transplant recipients.

Conclusion

Despite pretransplant sinus surgery, recolonization of lung grafts occurs commonly and rapidly with a spectrum of flora that mimics the sinus flora. Survival rates of CF patients who undergo prophylactic sinus surgery are similar to those from centers where prophylactic sinus surgery is not performed routinely. Pretransplant sinus surgery does not appear to prevent lung graft recolonization and is not associated with overall survival benefit.

Advances in Lung Transplantation for Patients Who Have Cystic Fibrosis

Transplantation in patients who have cystic fibrosis (CF) presents important challenges regarding candidate selection and preoperative management, technical obstacles in the perioperative period, the postoperative management of medical comorbidities related to CF, and the psychosocial impact of transplantation. This article outlines some of these challenges and describes recent advances in approaching this endeavor in patients who have CF.

Cardiopulmonary bypass for lung transplantation in cystic fibrosis: pilot evaluation of perioperative outcome

OBJECTIVE

The purpose of this study was to determine whether cardiopulmonary bypass (CPB) reduces the incidence of perioperative graft infection after lung transplantation in adults with cystic fibrosis (CF).

DESIGN

Retrospective and observational.

SETTING

University hospital.

PARTICIPANTS

Adults with CF who underwent lung transplantation (1998-2003).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Cohort size was 26: group A (n = 10) who underwent CPB for implantation of both lungs, group B (n = 8) who underwent CPB only for implantation of the second lung, and group C (n = 8) who did not undergo CPB. The 3 cohort subgroups were similar (p > 0.05) in demographics, preoperative lung function, and anesthetic management. Group A had a lower incidence of perioperative pneumonia (p = 0.02). CPB exposure increased transfusion (B > A > C) of fresh frozen plasma and platelets but not packed red blood cells. There were no differences (p > 0.05) in clinical outcome as reflected by duration of mechanical ventilation, tracheal re-intubation, re-exploration for bleeding, sepsis, primary graft dysfunction, renal dysfunction, length of stay, and mortality.

CONCLUSIONS

CPB is associated with decreased incidence of early graft infection after lung transplantation for adult CF when used for implantation of both lungs. This may be because of improved decontamination of the operative field before graft implantation.

Surgical management of pulmonary and gastrointestinal complications in children with cystic fibrosis

PURPOSE OF REVIEW

Cystic fibrosis is a common disorder, affecting as many as 1:2500 Caucasian live births. Despite improved medical management, disease-specific complications are common and are responsible for substantial morbidity and ultimately mortality. Both pulmonary and gastrointestinal complications of cystic fibrosis are well known; however, the complications requiring surgical intervention in the pediatric population are infrequent. We provide a detailed review of the cystic fibrosis-associated pulmonary and gastrointestinal complications and potential surgical options for management in children with cystic fibrosis.

RECENT FINDINGS

Recent operative approaches are described that include application of minimally invasive surgical techniques primarily for intrathoracic disease. Novel medical therapies are also presented. Finally an attempt is made to put in perspective those surgical care advances that have had a benefit on disease outcomes.

SUMMARY

This report will provide the physician caring for the child with cystic fibrosis an understanding of those disease complications that will require surgical consultation and potential operative intervention.

[Lung transplantation in cystic fibrosis: perioperative mortality]

OBJECTIVE

To determine the incidence and causes of perioperative mortality following lung transplant for cystic fibrosis.

PATIENTS AND METHODS

We analyzed the cases of 57 patients. Fifty-five patients received double lung transplants, 1 received a heart-double lung transplant, and 1 received a combined double lung and liver transplant. Information related to the organ donor, recipient, lung graft, and early postoperative period was gathered. Perioperative mortality was defined as death resulting from anesthesia or surgery regardless of how many days had passed. The Kaplan-Meier method was used to analyze survival. A Cox logistic regression model was used to determine variables affecting mortality.

RESULTS

Survival was 83.7% at 1 year after transplantation, 77.3% at 2 years, and 66.9% at 5 years. Five (8.7%) patients died as a result of anesthesia or surgery. A ratio of PaO2 to inspired oxygen fraction (FiO2) less than 200 mm Hg in the early postoperative period was observed in 8 (14%) patients. Primary graft failure occurred in 4 patients, due to pneumonia in 2 and to biventricular dysfunction in 2. Three of those patients died. Two patients with PaO2/FiO2 greater than 200 mm Hg died after surgery, one from septic shock due to Pseudomonas cepacia and the other from massive cerebral infarction. PaO2/FiO2 upon admission to the recovery care unit was the only variable significantly associated with perioperative mortality in the logistic regression model (P=.0034).

CONCLUSIONS

The only factor significantly related to perioperative mortality in patients receiving transplants for cystic fibrosis was PaO2/FiO2 upon admission to the recovery unit.

Multi-organ transplantation: is there a protective effect against acute and chronic rejection?

BACKGROUND

Heart-lung transplantation (Tx) is known to offer a protective effect against acute cardiac rejection. This study was undertaken to evaluate acute and chronic heart and/or lung rejection in the setting of multiple-transplanted organs from the same donor compared with single-organ transplantation.

METHODS

Acute (treated rejection episodes of heart or lungs) and chronic (allograft vasculopathy in hearts and bronchiolitis obliterans syndrome [BOS] in lungs) rejection events were analyzed in 348 heart transplant (H) recipients, 24 heart-lung (HL) recipients, 82 double-lung (L) recipients and 8 heart-kidney (HK) recipients >18 years of age, who were transplanted between 1990 and 2002.

RESULTS

Survival at 3 years differed among groups as follows: HK, 100%; H, 82%; HL, 74%; and L, 70%. The probability of acute rejection within the first 3 months was higher in H recipients than in HL (81% vs 22%; p < 0.0001) or HK (81% vs 12%; p = 0.00009) recipients. Acute cardiac rejection occurred more frequently during the first 2 years in isolated H recipients compared with HL (2.8 vs 0.27 episodes; p < 0.0001) and HK (2.8 vs 0.54; p < 0.001) recipients. Acute lung rejection occurred more frequently in the first 2 years in L than HL (2.4 vs 1.0 episodes; p = 0.02) recipients. Chronic cardiac rejection (allograft vasculopathy) was more likely within 3 years after H compared with HL (32% vs 16%; p = 0.04) or HK (32% vs 0%; p = 0.14). The onset of chronic lung rejection (BOS) within 3 years was similar in HL and L recipients (39% vs 40%; p = 0.9).

CONCLUSIONS

Recipients of multiple organs from a single donor undergo less acute rejection of the heart or lungs compared with isolated heart or lung transplant recipients. Cardiac allograft vasculopathy is decreased significantly when cardiac transplantation is combined with a lung allograft. A lower incidence of cardiac allograft vasculopathy is observed when cardiac transplantation is combined with a renal allograft, and may prove statistically significant when more cases have been accumulated. These phenomena may result from immune modulation of the recipient by simultaneous transplant of disparate tissues or introduction of immune-modulating hematopoietic elements.

Overexpression of Human Bcl-2 in Syngeneic Rat Donor Lungs Preserves Posttransplant Function and Reduces Intragraft Caspase Activity and Interleukin-1?? Production

BACKGROUND

A significant cause of primary graft failure in lung transplantation is ischemia-reperfusion (I/R). I/R injury generates proinflammatory cytokines, such as interleukin (IL)-1beta, and activates the caspase-mediated pathways of alveolar epithelial apoptosis. The authors investigated whether gene transfer of the human antiapoptotic protein Bcl-2 by means of intratracheal adenoviral administration would preserve posttransplant lung function and reduce intragraft activated caspase activity and IL-1beta production in syngeneic rat donor lung grafts.

METHODS

First, 1.0 x 10(9) plaque-forming units of AdvBcl-2 in phosphate-buffered saline (PBS), AdvNull empty vector in PBS, or PBS alone was administered intratracheally to ACI (RT1(a)) rats. Then, the left lungs were procured after 24 hr of in vivo incubation and orthotopically transplanted after 1 hr of cold ischemia into syngeneic recipients. After 2 hr of reperfusion, peak inspiratory pressures (PIP) and donor pulmonary vein PaO(2) was measured in all grafts; grafts were then excised and protein extracts were analyzed by enzyme-linked immunosorbent assay (ELISA) and activated caspase-3 and caspase-9 assays.

RESULTS

Human Bcl-2 transgene overexpression in donor lung grafts was demonstrated by ELISA of tissue homogenates. Pretreatment of donor lungs with AdvBcl-2 resulted in reduced PIP and increased lung isograft pulmonary vein PaO(2) compared with AdvNull or PBS-alone treated controls. In addition, AdvBcl-2 pretreatment led to diminished cytochrome c release into cytosolic extracts and reduced intragraft IL-1beta production and inhibited intragraft caspase-3 and caspase-9 activity.

CONCLUSIONS

Adenoviral overexpression of human Bcl-2 protein limits I/R injury in rat lung isografts. These data suggest that the use of Bcl-2 gene transfer to human lung donors may reduce the oxidative stress of pulmonary grafts after transplantation in clinical lung transplantation.

Cardiopulmonary transplantation: experience of a lung transplant group

Cardiopulmonary transplantation (CPT) is indicated for patients eligible for heart transplantation (HT) or lung transplantation (LT) who have severe concomitant lung or heart disease. Only 2 groups perform CPT in Spain. We report our experience with 18 CPTs representing 8.2% and 5% compared with LT (220) and HT (362), respectively, from February 13, 1990 to October 15, 2002. The mean time on a waiting list was 138 days. The current number of surviving patients is 7 (39%), with a mean follow-up of 602 days (range, 3 to 4627 days). They all remain asymptomatic with normal respiratory function in 4 patients. No cardiac graft rejection has been detected. Two patients experienced sustained gastroparesis during the first year with spontaneous resolution. Death occurred within the first 3 months in 9 patients. These outcomes contrast with the early mortality associated with LT and HT in our series, namely 10.6% and 11%, respectively. The different causes of death were as follows: sepsis and multiorgan failure in 5 patients, hemorrhagic shock in 3 patients, and suture dehiscence and fungal aortic perforation in 1 patient. Late mortalities were recorded in 2 cases. Overall patient survival in our series is lower than that reported by the International Registry (IR), with an early mortality rate of 50% (30% IR). Nevertheless, our survival rate at 10 years after transplantation is 30% (26% IR). We conclude that CPT should be considered despite the greater early morbidity and mortality.

27. Transplantation immunology: organ and bone marrow

The discovery of the human MHC in 1967 launched the field of organ and tissue transplantation. More than 800,000 such transplants have been performed during this time. Although matching of donor and recipient for MHC antigens was shown to be of great importance and continues to be so, the development of pharmacologic agents and antilymphocyte antibodies that interfere with the process of graft rejection has had a crucial role in the success of organ transplantation during the past 2 decades. Enormous progress has been made in understanding the immunologic mechanisms of graft rejection and of graft-versus-host disease. The roles of antibodies, antigen-presenting cells, helper and cytotoxic T cells, immune cell surface molecules, and signaling mechanisms and the cytokines they release have been clarified. This understanding is leading to the development of newer immunosuppressive agents targeting various components of the rejection process. Combinations of these agents work synergistically, leading to lower doses and reduced toxicity. Similarly, the development of effective T-cell depletion techniques has been of great importance for bone marrow transplantation when an HLA-identical sibling is not available. The major obstacle to the performance of solid organ transplantation currently is the shortage of donor organs.