Registry of the International Society for Heart and Lung Transplantation: twenty-second official adult lung and heart-lung transplant report--2005

High frequency of bronchogenic carcinoma after single-lung transplantation

BACKGROUND

Lung transplantation is a commonly employed therapy in the treatment of patients with advanced lung diseases related to tobacco use. Little is known about the long-term incidence or risk factors for primary lung cancer after lung transplantation. To determine the frequency, clinical features and risk factors for primary bronchogenic malignancy after lung transplantation, we designed a matched cohort study of single and bilateral lung transplant recipients with extended follow-up.

METHODS

We retrospectively reviewed the records of 262 lung transplant recipients who survived > or =90 days post-transplant and assessed for the development of primary lung cancer. One hundred thirty-one consecutive single-lung transplant (SLTx) recipients were matched to 131 consecutive bilateral lung transplant (BLTx) recipients by native disease. Risk factors for lung cancer development were derived using univariate and multivariate proportional hazards models.

RESULTS

Of the SLTx recipients, 6.9% developed primary lung cancer after transplantation as compared with 0% of the BLTx recipients (p = 0.002), after a mean of 52 months. Histologically, non-small-cell cancers were present in the native lung, which led to death in 67% (6 of 9) of the patients despite treatment. Significant risk factors for the development of primary lung cancer were increasing age (p = 0.004), >60-pack-year smoking history (p = 0.03), and SLTx as compared with BLTx (p < 0.001).

CONCLUSIONS

Single-lung transplant confers a significantly elevated risk of developing primary post-transplant lung cancer as compared with BLTx in patients with comparable native disease, age and tobacco history.

Impact of immediate primary lung allograft dysfunction on bronchiolitis obliterans syndrome

RATIONALE

Primary graft dysfunction is a common complication after lung transplantation and a significant risk factor for short- and long-term mortality.

OBJECTIVE

We examined the impact of primary graft dysfunction on bronchiolitis obliterans syndrome.

METHODS

We performed a retrospective cohort study of 334 adult lung transplant recipients at our program and graded the severity of primary graft dysfunction according to the International Society for Heart and Lung Transplantation definition. We evaluated the impact of primary graft dysfunction on acute rejection, lymphocytic bronchitis, and bronchiolitis obliterans syndrome stage 1, using univariable and multivariable Cox proportional hazards models.

MAIN RESULTS

Among the 334 recipients, 65 did not have primary graft dysfunction (grade 0), 130 had grade 1, 69 had grade 2, and 70 had grade 3. In the univariable analysis, all grades of primary graft dysfunction were associated with a significantly increased risk of bronchiolitis obliterans syndrome stage 1 (grade 1: relative risk [RR] = 1.73; grade 2: RR = 2.13; and grade 3: RR = 2.53, compared with grade 0). The multivariable model demonstrated that the increased risk of bronchiolitis obliterans syndrome associated with primary graft dysfunction was independent of acute rejection, lymphocytic bronchitis, and community-acquired respiratory viral infections. However, there was no association between primary graft dysfunction and acute rejection or lymphocytic bronchitis.

CONCLUSIONS

Primary graft dysfunction is associated with an increased risk of bronchiolitis obliterans syndrome independent of acute rejection, lymphocytic bronchitis, and community-acquired respiratory viral infections, and this risk is directly related to the severity of primary graft dysfunction.

Voriconazole prophylaxis in lung transplant recipients

Lung transplant recipients have one of the highest rates of invasive aspergillosis (IA) in solid organ transplantation. We used a single center, nonrandomized, retrospective, sequential study design to evaluate fungal infection rates in lung transplant recipients who were managed with either universal prophylaxis with voriconazole (n = 65) or targeted prophylaxis (n = 30) with itraconazole +/- inhaled amphotericin in patients at high risk (pre- or posttransplant Aspergillus colonization [except Aspergillus niger]). The rate of IA at 1 year was better in lung transplant recipients receiving voriconazole prophylaxis as compared to the cohort managed with targeted prophylaxis (1.5% vs. 23%; p = 0.001). Twenty-nine percent of cases in the targeted prophylaxis group were in patients colonized with A. niger who did not receive itraconazole. A three-fold or higher increase in liver enzymes was noted in 37-60% of patients receiving voriconazole prophylaxis as compared to 15-41% of patients in the targeted prophylaxis cohort. Fourteen percent in the voriconazole group as compared to 8% in the targeted prophylaxis group had to discontinue antifungal medications due to side effects. Voriconazole prophylaxis can be used in preventing IA in lung transplant recipients. Regular monitoring of liver enzymes and serum concentrations of calcineurin inhibitors are required to avoid hepatotoxicity and nephrotoxicity.

Vascular Endothelial Growth Factor Plays a Major Role in Development of Experimental Obliterative Bronchiolitis

Obliterative bronchiolitis (OB) is the major limitation for long-term survival of lung allograft recipients. The exact molecular and cellular mechanisms contributing to obliterative lesion formation are unknown. Pathological characteristics of OB are epithelial damage, peribronchial inflammation, and increasing obliteration of bronchioli. Vascular endothelial growth factor (VEGF) is an angiogenic growth factor that exerts proinflammatory effects by increasing endothelial permeability and inducing expression of endothelial adhesion molecules. We investigated the role of VEGF in the development of OB in rat tracheal allografts and the role of VEGF receptors (VEGFR)-1 and -2 in the development of OB in mouse tracheal allografts. In nontreated allografts, with increasing loss of epithelium and airway occlusion, VEGF messenger RNA (mRNA) and protein expression vanished in the epithelium and increased in smooth muscle cells and mononuclear inflammatory cells compared with syngeneic grafts. Intragraft VEGF overexpression by adenoviral transfer of a mouse VEGF164 gene led to a decrease in epithelial necrosis but increased luminal occlusion by >50% compared with AdLacZ-treated rat tracheal allografts. When compared with the control immunoglobulin (Ig)G group, simultaneous treatment with antibodies against VEGFR-1 and -2 significantly lowered the degree of luminal occlusion of mouse tracheal allografts.

Lung transplantation in patients 60 years and older: results, complications, and outcomes

BACKGROUND

Advanced recipient age is reported to negatively affect survival after lung transplantation (LTX). We hypothesized that LTX in patients aged > or = 60 years could be performed with acceptable outcomes.

METHODS

We identified 182 consecutive LTX recipients from 1995 to 2005. Outcomes were analyzed and survival compared with results in recipients aged < 60, as well as with United Network for Organ Sharing (UNOS) registry outcomes for the same age and study period. Actuarial survivals were calculated by the Kaplan-Meier method.

RESULTS

During the study period, 29% (52/182) of LTX recipients were > or = 60 years old (range, 60 to 69 years). Median follow-up was 2.9 years (range, 0 to 10 years). All patients but one received a single lung. Indications included chronic obstructive pulmonary disease in 63% (33/52), idiopathic pulmonary fibrosis in 27% (14/52), and other in 10% (5/52). In-hospital mortality was 12% (6/52) for those aged > or = 60 compared with 7% (9/130) for those aged < 60 (p = NS). Complications included reoperation in 10% (5/52), requirement for extracorporeal membrane oxygenation in 6% (3/52), renal failure in 12% (6/52), and stroke in 4% (2/52). Actuarial survivals at 30 days, and 1, 3, and 5 years were 90% (82, 98), 86% (76, 96), 71% (56, 85), and 55% (37, 73), respectively. No significant difference in survival was observed between age cohorts for our institutional data by Kaplan-Meier analysis (p = 0.34) or by Cox proportional hazard model (p = 0.15). A significant survival advantage was noted for our institution compared with UNOS for this cohort (p = 0.018).

CONCLUSIONS

In carefully selected recipients > or = 60 years of age, LTX offers acceptable outcomes and survival.

Reverse ventricular remodeling: mechanical options

PURPOSE OF REVIEW

The aim of this review is to update the cardiovascular clinician on the current status of surgical therapies aimed at achieving reverse ventricular remodeling.

RECENT FINDINGS

Relevant research focusing on mechanical options for reverse ventricular remodeling will be referenced and summarized.

SUMMARY

Heart failure is a tremendous burden on society in terms of both lives lost and healthcare costs. Knowledge of both medical and surgical therapies aimed at improving ventricular efficiency and reversing ventricular remodeling should be in the armamentarium of clinicians treating heart failure patients.

Marginal Lung Donors: A Diminishing Margin of Safety?

Lung donor shortages have resulted in the critical appraisal of cadaveric donor acceptability criteria and the gradual relaxation of once strict guidelines. Many centers have reported their results with these "extended criteria" donors and an increasing number of multicenter registry studies have also been published. The results have been contradictory and leave many questions unanswered. Important new data has however come to light since the last review of the subject by the International Society for Heart and Lung Transplantation Pulmonary Council. We review the current literature focusing on recent developments in the pursuit of an expanded lung donor pool with acceptable outcomes.

Initial Single-Center Experience With Sirolimus After Lung Transplantation

BACKGROUND

Standard immunosuppression after lung transplantation includes calcineurin inhibitors, mycophenolate mofetil, and steroids. Long-term survivors of lung transplantation are often confronted with chronic kidney disease, by definition related to the intake of calcineurin inhibitors. Sirolimus has been increasingly proposed as an alternative immunosuppressive agent due to its absence of nephrotoxicity, which could be used in selected patients.

METHODS

We prospectively administered sirolimus as an alternative to calcineurin inhibitors in 10 lung transplantation recipients with persistent drug nephrotoxicity. They were switched from tacrolimus to sirolimus. Four patients also had bronchiolitis obliterans syndrome. The conversion scheme consisted of an immediate stop of tacrolimus and an 6 to 8-mg loading dose of sirolimus, followed by 4 mg/d. After 5 days, the sirolimus dose was adjusted to maintain trough levels between 12 and 18 ng/mL or 6 and 12 ng/mL for combined sirolimus and tacrolimus. Patients were monitored for renal and graft function as well as clinical status.

RESULTS

A significant decrease in creatinine was observed after 1 week of treatment (P = .011). Azotemia decreased after 1 month, remaining stable (P < .01). Pulmonary function tests did not show significant modification from before sirolimus, inception in patients with or without bronchiolitis obliterans syndrome. There were seven infections. One patient died of complications related to bronchiolitis obliterans.

CONCLUSION

Sirolimus was a useful alternative immunosuppressant, allowing significant tacrolimus withdrawal in transplant recipients with renal impairment. Sirolimus administration allowed recovery of renal function with low morbidity; it was useful for rescue of chronic renal impairment after lung transplantation.

Morphometric examination of native lungs in human lung allograft recipients

The aim of the study was to estimate the degree of lung damage in patients with alpha(1)-antitrypsin (alpha1AT) deficiency, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) at the time of lung transplantation. Using unbiased stereological methods, lung-, bronchial- and vessel-volume, capillary length, and alveolar surface area and densities were estimated in recipient lungs from 21 consecutive patients with pre-transplant diagnoses including COPD (n=7), alpha1AT deficiency (n=6) and CF (n=8). Six unused adult donor lungs served as controls. Information relating to patient demography and pre-transplant lung function was obtained by retrospective chart review. Disease groups differed significantly with respect to demographics and pre-transplant lung function. Total lung volume was similar in all groups. Bronchial volume was significantly larger in CF patients compared to the control group (p<0.0001) and to the other two diagnostic groups: alpha1AT deficiency (p=0.0001) and COPD (p<0.0001). Alveolar surface density and capillary length density were significantly lower in patients with alpha1AT deficiency and COPD compared to controls (p<0.0001, respectively) and to patients with CF (p<0.0002, respectively). There were no correlations between clinical lung function and morphometric measurements. We conclude that unbiased microscopic stereological morphometry is an evolving science with the potential to elucidate pulmonary disease pathogenesis.

Lung Transplantation: Advances in Immunosuppression

Since the advent of various novel immunosuppressants, including tacrolimus, rapamycin, and daclixumab. expanding variations of protocols have been developed. Little evidence exists to substantially support a single agent over another. or a combination regimen protocol over another. Therefore, the principles and the goals of immunosuppression in lung transplantation recipients will remain moving targets and continue to evolve, and the use of large-scale, multi-institutional clinical trials is imperative to develop optimal immunosuppressive strategies.

Bilateral native lung–sparing lobar transplantation in a canine model

OBJECTIVE

Bilateral living-donor lobar lung transplantation has become an accepted approach in response to the cadaveric lung donor shortage. Because only one lobe is implanted in each chest cavity, this procedure is usually confined to patients of small size. The purpose of this study was to develop a technique of bilateral native lung-sparing lobar transplantation that can be applied to large adult patients.

METHODS

Bilateral native lung-sparing lobar transplantation was performed in 12 pairs of dogs. In donor animals the right middle, lower, and cardiac lobes were separated as a right graft, and the left lower lobe was separated as a left graft. In recipient animals these 2 grafts were implanted in the natural anatomic position with sparing native right upper, left upper, and middle lobes. In an acute study (n = 6), transplanted graft function was assessed for 3 hours after ligation of the pulmonary artery branches to the native spared lobes. In a chronic study (n = 6) the immunosuppressed recipients were observed for 3 weeks to assess the quality of bronchial healing and long-term pulmonary function.

RESULTS

Morphologic adaptation of the 2 grafts was found to be excellent. All 6 animals in the acute study showed excellent pulmonary function. Five of 6 animals in the chronic study survived for 3 weeks, with excellent pulmonary function and satisfactory bronchial healing.

CONCLUSION

Bilateral native lung-sparing lobar transplantation was technically possible and associated with excellent pulmonary function and good bronchial healing in a canine experimental model.

Macrophages in experimental rat lung isografts and allografts: infiltration and proliferation in situ

Alveolar macrophages (AMs) and peribronchial/perivascular macrophages are probably involved in lung allograft damage. We investigate leukocyte infiltration into graft tissue and address the question whether proliferation in situ contributes to macrophage homeostasis and accumulation. Lung transplantation was performed in the Lewis (LEW)-to-LEW and in the Dark Agouti-to-LEW rat strain combination. Graft infiltration by ED1+ and ED2+ (CD163) macrophages was analyzed by immunohistochemistry (IHC) and compared with infiltration by lymphocytes. Cells in the S-phase of the cell cycle were pulse-labeled with BrdU and detected immunohistochemically. Finally, the donor or recipient origin of AMs was determined by IHC and in situ hybridization. ED1+ AMs in allogeneic transplants increased by more than 25-fold from Days 1 to 5. In addition, large, peribronchial/perivascular infiltrates developed containing numerous ED1+ cells. Although AMs in normal rat lungs are CD163-, AMs up-regulated CD163 between Days 4 and 5, reaching maximum values on Day 6. Lymphocytes were less numerous than macrophages. About 16% of the AMs and 10% of the peribronchial/perivascular macrophages were in the S-phase of the cell cycle on Day 2 post-transplantation. No differences in the frequency of BrdU+ macrophages were obvious between isografts and allografts. AMs of donor origin increased in number considerably during allograft rejection. In conclusion, the cellular infiltrate in lung allografts is dominated by macrophages, which exhibit an unusual phenotype and a strong capacity for mitotic self-renewal.

Preliminary report of the safety and efficacy of hyperbaric oxygen therapy for specific complications of lung transplantation

BACKGROUND

Lung transplantation (LTx) is a complex therapy requiring immunosuppression and is associated with significant infective morbidity and mortality. Hyperbaric oxygen (HBO) therapy has been used successfully in the treatment of specific serious infections, ischemic injuries and cerebral arterial gas embolism. The purpose of this study was to evaluate the efficacy and safety of HBO therapy after LTx, generally as indicated for refractory infectious complications.

METHODS

This investigation was a retrospective study of all lung transplant recipients treated with HBO therapy at the Alfred Hospital between March 1990 and August 2005.

RESULTS

In this study we describe 9 patients (1.7%) from a total of 544 overall lung transplants performed over the period. Indications included: sternal osteomyelitis (n = 4); refractory cellulitis (n = 2); refractory septic arthritis (n = 1); ischemic toes (n = 1); and cerebral arterial gas embolism (n = 1). The patients received 1 to 25 HBO treatments at 100% Fio(2) and 100 to 180 kPa for 100 minutes per treatment. The treatment was generally well tolerated, although 2 patients ceased therapy prematurely due to a seizure and ear barotrauma (n = 1 each). Five patients had complete resolution of these life-threatening complications. Long-term survival and graft function were excellent, although graft function temporarily fell.

CONCLUSIONS

HBO is a safe therapy for traditional HBO indications after LTx and appears useful, particularly in the management of infectious complications, whereas other therapies have failed or are contraindicated.

Racial and ethnic disparities in idiopathic pulmonary fibrosis: A UNOS/OPTN database analysis

We previously reported poorer survival among non-Hispanic blacks and Hispanics with idiopathic pulmonary fibrosis (IPF) compared to non-Hispanic whites at our center. In the current study, we hypothesized that these disparities would exist in a nationwide cohort of wait-listed patients with IPF. We performed a retrospective cohort study of 2635 patients with IPF listed for lung transplantation between 1995 and 2003 at 94 transplant centers in the United States. The age-adjusted mortality rate was higher among non-Hispanic blacks [hazard ratio (HR) = 1.24, 95% confidence interval (CI) 1.06-1.45, p = 0.009] and Hispanics (HR = 1.29, 95% CI 1.06-1.56, p = 0.01) compared to non-Hispanic whites. These findings persisted after adjustment for transplantation, medical comorbidities and socioeconomic status. Worse lung function at the time of listing appeared to explain some of these differences (HR for non-Hispanic blacks after adjustment for forced vital capacity percent predicted = 1.16, 95% CI 0.98-1.36, p = 0.09; HR for Hispanics = 1.21, 95% CI 0.99-1.48, p = 0.056). In summary, black and Hispanic patients with IPF have worse survival than whites after listing for lung transplant.

Evaluation of Patients Referred for Lung Transplantation: Fourteen Years Experience

We present a descriptive study of patients referred as candidates for lung transplantation in the last 14 years. The 837 requests were evaluated stepwise in three phases: phase I, derivation report; phase II, outpatient evaluation; and phase III, inpatient evaluation. Chronic obstructive pulmonary disease was the most common reason for referral (31%). Cystic fibrosis was the referral disease with the best transplanted/referred relation (57%) and pulmonary fibrosis was the disease that had the highest mortality (39.7% of all deaths). Forty-three percent of all patients reached phase III and 29% were transplanted. Mortality on the waiting list was 3.7%. The most important causes of exclusion were inadequate indications and the presence of severe associated diseases. The mean study was 44 days. Knowledge of the natural history, local factors that influence organ availability, expected time on the waiting list, and disease progression allow optimization of this therapeutic option.

The Preoperative Evaluation of the Transplanted Patient for Nontransplant Surgery

With the improved success of solid-organ transplantation, there has been an increased willingness to transplant individuals previously felt to be unsuitable for such procedures. Factors such as age and various medical comorbidities are no longer considered contraindications to transplantation, and hence, an increasing number of recipients may require medical care not specifically related to the transplant. After transplantation, many of these patients may require elective or emergent surgery, making it important for all surgeons to be familiar with the factors that may influence surgical outcomes in this population, asa well asa factors that affect postoperative care. Most transplant centres use a team approach to manage these complex patients, relying on medical professionals experienced in their care and management. Close interaction with the transplant team is likely the single most important step in preparing the transplanted patient for surgery and managing their postoperative care.

Six-minute-walk distance predicts waiting list survival in idiopathic pulmonary fibrosis

RATIONALE

Functional studies may be useful to predict survival in idiopathic pulmonary fibrosis (IPF). Various cutoffs of 6-min-walk distance (6MWD) have been suggested to identify patients at a high risk of death.

OBJECTIVES

To examine the association between 6MWD and survival in patients with IPF listed for lung transplantation, and to identify sensitive and specific cutoffs for predicting death at 6 mo.

METHODS

We performed a retrospective cohort study of 454 patients classified as having IPF listed for lung transplantation with the United Network for Organ Sharing between June 30, 2004 and July 22, 2005.

MEASUREMENTS AND MAIN RESULTS

Lower 6MWD was associated with an increased mortality rate (p value for linear trend < 0.0001). Patients with a walk distance less than 207 m had a more than fourfold greater mortality rate than those with a walk distance of 207 m or more, despite adjustment for demographics, anthropomorphics, FVC % predicted, pulmonary hypertension, and medical comorbidities (adjusted rate ratio, 4.7; 95% confidence interval, 2.5-8.9; p < 0.0001). 6MWD was a significantly better predictor of 6-mo mortality than was FVC % predicted (c-statistic = 0.73 vs. 0.59, respectively; p = 0.02).

CONCLUSIONS

Lower 6MWD was strongly and independently associated with an increased mortality rate for wait-listed patients classified as having IPF. 6MWD was a better predictor of death at 6 mo than was FVC % predicted.

Respiratory viral infection in obliterative airway disease after orthotopic tracheal transplantation

BACKGROUND

The long-term survival after human lung transplantation is limited by bronchiolitis obliterans syndrome (BOS). Clinically, community-acquired respiratory viral infections have been correlated with an increased incidence of BOS. The goal of this study was to investigate the role of respiratory viral infections in chronic lung allograft rejection using the murine orthotopic tracheal transplantation model.

METHODS

Eighty orthotopic tracheal transplants were performed using BALB/c and C57BL/6 mice. Recipient mice were infected intranasally with Sendai virus (SdV), a murine parainfluenza type I virus. Experiments altering the infectious dose, infection time, harvest time, allogeneic response, and viral response were performed. Tracheal allograft rejection was monitored using percent fibrosis and lamina propria to cartilage ratio measurements. Interferon-gamma ELISPOT analysis against irradiated donor (BALB/c) splenocytes was used as immunologic indicator of alloreactivity after transplantation.

RESULTS

Sendai virus infection revealed a dose-dependent transient suppression of alloreactivity with a decrease in tracheal allograft fibrosis and frequency of alloreactive T cells at 30 days. This immunosuppression was reversed by day 60, leading to increased tracheal allograft fibrosis with a concomitant increase in the frequency of interferon-gamma producing alloreactive T cells. Pretransplant sensitization with donor antigens prevented the initial suppression of alloreactivity due to SdV infection. Furthermore, pretransplant immunization against SdV infection resulted in rapid clearing of the infection and reduced the immunopathology of rejection.

CONCLUSIONS

Respiratory viral infections can cause enhanced tracheal allograft rejection despite the initial phase of transient immunosuppression. Early treatment or vaccination against the respiratory infections may represent a viable intervention to reduce the risk of chronic rejection.

Pediatric lung transplantation

Lung transplantation in children has been performed since the early 1990s. The indications are cystic fibrosis, pulmonary vascular disease, and a variety of other pulmonary problems leading to death in small children. These other diseases include abnormalities in the metabolism of surfactant producing severe respiratory insufficiency in newborn infants. Many problems accompany these patients before transplantation and many problems are produced both by the transplant itself and immunosuppressant drugs which these children are obliged to take following transplantation. Nonetheless, lung transplantation offers the only real hope of survival in many instances. The long-term results have been somewhat discouraging with a 5-year survival of approximately 50%. The major causes of mortality late following lung transplantation are bronchiolitis obliterans, infections, and malignancy. The development of newer immunosuppressant drugs may offer hope for better results in the future.

Adenovirus mediated IL-10 gene transfer to the airway of the rat lung for prevention of lung allograft rejection

BACKGROUND

The ability to express genes with potential immunoregulatory capacity could reduce allograft rejection (AR). We examined the feasibility of transferring the viral interleukin-10 (vIL-10) gene into rat lungs by intra-bronchial instillation and the subsequent effects of delivered vIL-10 on acute lung AR.

METHODS

First, the adenoviral beta-galactosidase vector (adv-beta-gal) particles were instilled into the airway of the rat lung and protein synthesis of beta-gal was examined by histochemical staining. Next, the ability of the adenoviral vIL-10 vector (adv-vIL-10) transfection to modify AR was examined in a highly histoincompatible rat lung transplant model (BN-->Lew). Donor left lungs were transfected with 3 x 10(8) pfu/0.3 mL of adv-vIL-10 (vIL-10 group) or adv-beta-gal (control group) 3 days before transplantation. On day 6 post-transplant, lung allografts were harvested and AR was graded histologically (stage 0-4). Several pathological categories of inflammation (perivascular, peribronchial, or peribronchiolar mononuclear infiltrates, edema, vasculitis, intraalveolar hemorrhage, and necrosis) were also examined and scored on a scale of 0-4 as previously described.

RESULTS

A successful transgene protein synthesis by adv-beta-gal in alveolar epithelial cells and alveolar macrophages was confirmed by histochemical staining with X-gal. The vIL-10 group showed a trend toward an improved stage of AR (3.75 +/- 0.5 vs. 4.0 +/- 0), and also a decreased pathological scores for edema (3.5 +/- 0.6 vs. 4.0 +/- 0), intraalveolar hemorrhage (2.3 +/- 1.0 vs. 2.5 +/- 0.6) and necrosis (1.5 +/- 0.5 vs. 1.75 +/- 1.3) compared with the control group, however, the differences in any pathological scores between the two groups did not reach a statistical significance.

CONCLUSIONS

1. A successful transgene protein synthesis in alveolar epithelial cells was ensured by intra-bronchial instillation of an adenoviral vector encoding beta-galactosidase gene. 2. Transferring the vIL-10 gene into rat lungs by intra-bronchial instillation did not seem to reduce lung AR significantly, as opposed to the results of our previous experiments in a rat cardiac allograft model. This discrepancy may be explained by several potential factors including the immunogenecity of adenoviral vectors in conjunction with the nature of the lung more susceptible to immune response and inflammation.

Cyclosporine C2 Target Levels and Acute Cellular Rejection After Lung Transplantation

BACKGROUND

Acute pulmonary allograft rejection (AR) is the most important risk factor for bronchiolitis obliterans syndrome (BOS), which is associated with reduced quality of life and decreased survival after lung transplantation (LTx). Trough (C0) cyclosporine (CyA) levels have a poor correlation with area-under-the-curve (AUC) measurements of cyclosporine exposure compared with 2-hour post-dose (C2) levels, but there are no published guidelines for C2 levels after LTx. Hence, we assessed the utility of C2 target levels to prevent AR.

METHODS

Fifty consecutive de novo LTx patients (bilateral, 44; single, 3; heart-lung, 3; cystic fibrosis, 20; non-cystic fibrosis, 30) managed with CyA were assigned target C2 levels as follows: >800 microg/liter within 48 hours; >1,200 microg/liter from Week 1 to Month 1; >1,000 microg/liter in Month 2; >800 microg/liter in Month 3; >700 in microg/liter in Months 3 to 6; and >600 microg/liter thereafter. Surveillance transbronchial biopsies (TBBxs) were performed at 3, 6, 9 and 12 weeks. An intention-to-treat analysis was performed and results compared with our historic controls managed by C0 monitoring.

RESULTS

Fifteen of 50 (30%) LTx recipients developed AR on 23 of 171 TBBxs (Grade A2:A3 = 21:2) during follow-up (mean +/- SD) of 1,185 +/- 426 days (range, 16 to 1,790 days). Eighteen of 23 AR episodes occurred after sub-target C2 levels. The 30-day, 1-, 3- and 5-year actuarial survival rates were 98%, 94%, 82% and 77%, respectively. Thirteen of 48 (27%) evaluable LTx recipients developed BOS with 1-, 3- and 5-year freedom-from-BOS rates of 96%, 79% and 59%, respectively. Only 1 patient developed severe renal dysfunction.

CONCLUSIONS

Achieving and maintaining target C2 levels after LTx is associated with reduced rates of AR and BOS, preservation of renal function, and excellent short-term survival rates when compared with historic controls.

CXCR3 and its ligands in a murine model of obliterative bronchiolitis: regulation and function

Lung transplantation remains the only effective therapy for patients with end-stage lung disease, but survival is limited by the development of obliterative bronchiolitis (OB). The chemokine receptor CXCR3 and two of its ligands, CXCL9 and CXCL10, have been identified as important mediators of OB. However, the relative contribution of CXCL9 and CXCL10 to the development of OB and the mechanism of regulation of these chemokines has not been well defined. In this study, we demonstrate that CXCL9 and CXCL10 are up-regulated in unique patterns following tracheal transplantation in mice. In these experiments, CXCL9 expression peaked 7 days posttransplant, while CXCL10 expression peaked at 1 day and then again 7 days posttransplant. Expression of CXCL10 was also up-regulated in a novel murine model of lung ischemia, and in bronchoalveolar lavage fluid taken from human lungs 24 h after lung transplantation. In further analysis, we found that 3 h after transplantation CXCL10 is donor tissue derived and not dependent on IFN-gamma or STAT1, while 24 h after transplantation CXCL10 is from recipient tissue and regulated by IFN-gamma and STAT1. Expression of both CXCL9 and CXCL10 7 days posttransplant is regulated by IFN-gamma and STAT1. Finally, we demonstrate that deletion of CXCR3 in recipients reduces airway obliteration. However, deletion of either CXCL9 or CXCL10 did not affect airway obliteration. These data show that in this murine model of obliterative bronchiolitis, these chemokines are differentially regulated following transplantation, and that deletion of either chemokine alone does not affect the development of airway obliteration.

Update of early respiratory failure in the lung transplant recipient

PURPOSE OF REVIEW

Respiratory failure remains the most common complication in the perioperative period after lung transplantation. Consequently it is important to develop an approach to diagnosis and the treatment of respiratory failure in this population. This review highlights the advances made in the understanding and treatment of lung transplant patients in the early postoperative phase. Owing to its relative importance, advances in the understanding and treatment of ischaemia-reperfusion injury are highlighted.

RECENT FINDINGS

The causes of respiratory failure and the complications seen after transplantation are time dependent, with ischaemia-reperfusion, infection, technical problems and acute rejection being the most common in the early perioperative phase, and obliterative bronchiolitis, rejection, and infections secondary to bacteria, fungi, and viruses becoming more prevalent after 3 months. The advances in lung preservation and postoperative care may be overshadowed by an increase in the complexity of the recipients and the use of more marginal organs. An improved mechanistic understanding of ischaemia-reperfusion injury has translated into potential therapeutic targets. The development of prospective clinical trials, however, is hampered by a relatively small sample of patients and a significant degree of heterogeneity in the lung transplant population.

SUMMARY

Many advances have been made in the understanding of ischaemia-reperfusion injury. Owing to the acute and long-term implications of this complication, interventions that reduce the risk of developing ischaemia-reperfusion need to be evaluated in prospective clinical trials.

Impact of Warm Ischemia on Different Leukocytes in Bronchoalveolar Lavage From Mouse Lung: Possible New Targets to Condition the Pulmonary Graft From the Non–Heart-Beating Donor

BACKGROUND

The use of non-heart-beating donors (NHBDs) for lung transplantation is a possible alternative for increasing the number of organs available. The warm ischemic period after circulatory arrest may contribute to a higher degree of primary graft dysfunction, resulting from ischemia-reperfusion injury (IRI). A better understanding of the role of inflammatory cells during the warm ischemic interval may be useful for developing new therapeutic strategies against IRI.

METHODS

Mice were divided in 7 groups (n = 6/group). In 3 groups, ischemia was induced by clamping the hilum of the left lung for 30, 60 or 90 minutes (Groups [30I], [60I] or [90I], respectively). In 3 more groups, the lung was reperfused for 4 hours after identical ischemic intervals (Groups [30I+R], [60I+R] or [90I+R], respectively). Surgical impact was evaluated in a sham group ([sham]). Total and differential cell counts and interleukin-1beta (IL-1beta) protein levels in bronchoalveolar lavage (BAL) were determined and their correlations were investigated.

RESULTS

Total cell, macrophage and lymphocyte numbers and IL-1beta protein levels increased progressively with longer ischemic intervals. A significant rise in BAL macrophages and lymphocytes was observed between [60I] and [90I] (p < 0.01 and p < 0.001, respectively). BAL neutrophils only increased after reperfusion with longer ischemic intervals. A positive correlation was found in the ischemic groups between IL-1beta levels and the number of macrophages (r = 0.62; p = 0.0012) and the number of lymphocytes (r = 0.68; p = 0.0002). A positive correlation was found in the reperfusion groups between IL-1beta levels and the number of neutrophils (r = 0.48; p = 0.044).

CONCLUSIONS

This study demonstrates for the first time that BAL macrophages and lymphocytes increase significantly during warm ischemia and correlate with IL-1beta levels.

Outcomes of patients with interstitial lung disease referred for lung transplant assessment

BACKGROUND

Patients with interstitial lung disease (ILD) very frequently die before the opportunity to receive lung transplantation (LTx). This retrospective study describes the clinical course of 86 patients with ILD referred for LTx assessment between January 1999 and December 2002.

AIMS

(i) To describe the outcomes, (ii) to identify reasons of delay to transplantation, (iii) to describe the causes of death/complications and (iv) to assess the pathological diagnosis and concordance with explanted lung pathology.

METHODS

Data were collected from the case notes of all patients with ILD referred to the Alfred Hospital over a 4-year period.

RESULTS

Twenty women and 66 men, mean age of 55 +/- 8 years, were referred for LTx assessment. Forty-five patients were deemed not suitable for LTx and 41 were listed. Twenty-two patients underwent transplantation, 16 died on the waiting list and 7 are still on the waiting list. Complications were frequent (e.g. pulmonary embolism, malignancy and infection) and carried high mortality. Patients dying on the waiting list appeared generally to be in accelerated decline, dying shortly after listing, with no evidence in their lung function test assessment predicting them as a poor prognosis group.

CONCLUSIONS

Serious complications and death on the waiting list of patients with idiopathic pulmonary fibrosis are high, not apparently because of delayed referral but usually in patients undergoing very rapid decline.

Lung Transplantation: Current Status and Challenges

The lung is an anatomically complex vital organ whose normal physiology depends on actively regulated ventilation and perfusion, and maintenance of a delicate blood-air barrier over a huge surface area in direct contact with a potentially hostile environment. Despite significant progress over the past 25 years, both short- and long-term outcomes remain significantly inferior for lung recipients relative to other "solid" organs. This review summarizes the current status of lung transplantation so as to frame the principle challenges currently facing end-stage lung-failure patients and the practitioners who care for them.

Azithromycin reduces airway neutrophilia and interleukin-8 in patients with bronchiolitis obliterans syndrome

RATIONALE

Bronchiolitis obliterans syndrome (BOS) remains the leading cause of death after lung transplantation. Treatment is difficult, although azithromycin has recently been shown to improve FEV(1). The exact mechanism of action is unclear.

HYPOTHESES

(1) Azithromycin reduces airway neutrophilia and interleukin (IL)-8 and (2) airway neutrophilia predicts the improvement in FEV(1).

METHODS

Fourteen lung transplant patients with BOS (between BOS 0-p and BOS 3) were treated with azithromycin, in addition to their current immunosuppressive treatment. Before and 3 mo after azithromycin was introduced, bronchoscopy with bronchoalveolar lavage (BAL) was performed for cell differentiation and to measure IL-8 and IL-17 mRNA ratios.

RESULTS

The FEV(1) increased from 2.36 (+/- 0.82 L) to 2.67 L (+/- 0.85 L; p = 0.007), whereas the percentage of BAL neutrophilia decreased from 35.1 (+/- 35.7%) to 5.7% (+/- 6.5%; p = 0.0024). There were six responders to azithromycin (with an FEV(1) increase of > 10%) and eight nonresponders. Using categorical univariate linear regression analysis, the main significant differences in characteristics between responders and nonresponders were the initial BAL neutrophilia (p < 0.0001), IL-8 mRNA ratio (p = 0.0009), and the postoperative day at which azithromycin was started (p = 0.036). There was a significant correlation between the initial percentage of BAL neutrophilia and the changes in FEV(1) after 3 mo (r = 0.79, p = 0.0019).

CONCLUSION

Azithromycin significantly reduces airway neutrophilia and IL-8 mRNA in patients with BOS. Responders have a significantly higher BAL neutrophilia and IL-8 compared with nonresponders and had commenced treatment earlier after transplantation. BAL neutrophilia can be used as a predictor for the FEV(1) response to azithromycin.

IL-12 p80 is an innate epithelial cell effector that mediates chronic allograft dysfunction

RATIONALE

Bronchiolitis obliterans syndrome is the leading cause of chronic lung allograft dysfunction. We have demonstrated that respiratory viral infection is a bronchiolitis obliterans syndrome risk factor and virus-dependent injury induces expression of innate airway epithelial genes belonging to the interleukin (IL)-12 family. Thus, we hypothesized that epithelial cell IL-12 family members could mediate lung allograft dysfunction.

OBJECTIVES

We used mouse and human allograft specimens to evaluate the role of epithelial cell IL-12 family members in allograft dysfunction associated with and without viral infection.

METHODS

Murine and human IL-12 family members were characterized and manipulated in allografts and then correlated with epithelial cell injury, immune cell accumulation, and collagen deposition.

RESULTS

In a mouse model of lung transplantation, concurrent viral infection and allogeneic transplantation increased epithelial injury and this was followed by exaggerated accumulation of macrophages and collagen deposition. This virus-driven allograft dysfunction was associated with an epithelial innate response manifested by a synergistic increase in the production of the macrophage chemoattractant IL-12 p80 (p80), but not IL-12 or IL-23. Blockade or overexpression of donor epithelial p80 resulted in a corresponding abrogation or enhancement of macrophage accumulation and allograft dysfunction. We extended these findings to human recipients with viral infection and transplant bronchitis and again observed excessive epithelial p80 expression that correlated with increased macrophage accumulation.

CONCLUSIONS

These experiments support a role for an enhanced epithelial innate response as a central process in allograft dysfunction and identify the macrophage chemoattractant p80 as an innate epithelial effector of disease progression.

Psychosocial Issues in the Assessment and Management of Patients Undergoing Lung Transplantation

This review examines psychosocial issues among lung transplant patients from the time of assessment through the posttransplant period. Although psychological factors are recognized as being important in the transplant evaluation, no standard approach to psychological assessment currently exists. Lung transplant candidates often experience high levels of psychological distress while awaiting transplant, and both pretransplant and posttransplant psychological functioning have been found to predict posttransplant quality of life, adherence to treatment, and, in some cases, medical outcomes. Given the limited long-term survival following transplantation, improving psychosocial functioning is essential for enhancing outcomes among lung transplant recipients. This review summarizes the extant literature on the psychosocial factors in lung transplantation and highlights several innovative efforts to improve psychological outcomes in this challenging patient population.

Cytokine Profile After Lung Transplantation: Correlation With Allograft Injury

BACKGROUND

Post-lung transplant reperfusion edema (PLTRE) and its more severe form, primary graft failure (PGF), occur in 10% to 60% of lung transplant recipients. We hypothesized that PLTRE and PGF would be associated with an elevated proinflammatory cascade and that the allograft would be the source of cytokine appearance in the circulation.

METHODS

Pulmonary arterial and systemic arterial samples were obtained at baseline and at 4, 8, and 24 hours after reperfusion. Post-lung transplant reperfusion-edema and PGF were defined as PaO2/FiO2 less than 300 with a mild or moderate infiltrate, or less than 200 with a severe infiltrate and ventilator dependence after 72 hours, respectively. Tumor necrosis factor alpha (TNFalpha), interleukin (IL)-6, IL-8, and IL-10 concentrations were determined by immunoassay.

RESULTS

Fifteen single and 6 bilateral lung recipients were studied. Six (29%) had PLTRE and 4 (19%) had PGF; these patients had an overall elevation in plasma IL-6, IL-8, and IL-10 concentrations (all p < 0.05). Subgroup analysis revealed a significantly greater elevation in IL-6, IL-8, and IL-10 levels in PGF patients (all p < 0.01) versus PLTRE. In the PGF group, TNFalpha and IL-10 concentrations were significantly greater in the systemic versus the pulmonary arterial samples (p < 0.05).

CONCLUSIONS

Patients with PLTRE and PGF exhibited graded increases in IL-6, IL-8, and IL-10 concentrations. The PGF patients had higher TNFalpha and IL-10 systemic arterial concentrations overall, consistent with the allograft being a source of this cytokine production.

Lung transplantation in Australia: barriers to translating new evidence into clinical practice

Evidence "beyond reasonable doubt" may never be achievable for low-volume drugs.

Immunoglobulin G levels before and after lung transplantation

RATIONALE

The determinants of immunoglobulin G (IgG) level and the risk of hypogammaglobulinemia (HGG) in patients with severe lung disease before and after lung transplantation are unknown.

OBJECTIVES

We aimed to identify predictors of low IgG levels before and after lung transplantation.

METHODS

We performed a retrospective cohort study of 40 consecutive lung transplant recipients at our center. Total IgG levels were measured before and serially after transplantation. Mild HGG was defined as IgG levels from 400-699 mg/dl; severe HGG was defined as IgG levels<400 mg/dl.

MEASUREMENTS AND MAIN RESULTS

Before transplantation, six (15%) patients had mild HGG, and none had severe HGG. Patients with chronic obstructive pulmonary disease had lower IgG levels compared with patients with other diseases (independent of corticosteroid use and age; p=0.001) and an increased risk of mild HGG (p=0.005). The cumulative incidences of mild and severe HGG significantly increased after transplantation (58 and 15%, respectively, both p<0.04 compared with pretransplant prevalences). Lower pretransplant IgG level and treatment with mycophenolate mofetil were associated with lower IgG levels after transplantation (both p<0.05). Only lower pretransplant IgG levels were significantly associated with an increased risk of severe HGG after transplantation (p=0.02).

CONCLUSIONS

Mild HGG is common in patients with severe chronic obstructive pulmonary disease, and the incidences of mild and severe HGG increase significantly early after lung transplantation. Baseline IgG levels and treatment with mycophenolate mofetil affect post-transplant IgG levels.