Results of lung transplantation in idiopathic pulmonary fibrosis patients

The Effect of Blood Transfusion in Lung Donors on Recipient Survival

BACKGROUND

Blood transfusion can have detrimental effects on the pulmonary system, leading to lung injury and respiratory decompensation with subsequent increased morbidity and mortality in surgical and critically ill patients. How much of this effect is carried from a lung donor to transplant recipient is not fully understood, raising questions regarding transplant suitability of lungs from transfused donors.

METHODS

United Network for Organ Sharing data were reviewed. Lung transplants from adult donors and known donor transfusion status were included; multiorgan transplants and retransplants were excluded. Recipient mortality was evaluated based on donor and recipient characteristics using a Kaplan-Meier survival estimate, Cox proportional hazards, and logistic regression models. We further assessed whether recipient mortality risk modified the donor transfusion effect.

RESULTS

From March 1996 to June 2017, 20,294 transplants were identified. Outcome analysis based on transfusion status showed nonsignificant difference in 1-year mortality (P = .214). Ninety-day recipient mortality was significantly higher with transfusion of >10 units (U) vs 1-10 U or no transfusion (8.5%, 6.1%, and 6.0%, respectively, P = .005). Multivariable analysis showed increased 90-day mortality with transfusion of >10 U compared to no transfusion (odds ratio 1.62, P < .001), whereas 1-10 U showed no difference (odds ratio 1.07, P = .390). When stratified by recipient transplant risk, transfusion of >10 U was associated with increased mortality even with the lowest-risk recipients, while transfusion of 1-10 U showed no mortality increase even in the highest-risk recipients.

CONCLUSIONS

Donor transfusion of >10 U of blood was associated with increased 90-day recipient mortality even in low-risk transplants. This risk should be considered when evaluating donor lungs.

Comparison of mechanical cardiopulmonary support strategies during lung transplantation

INTRODUCTION

Lung transplantation outcomes are influenced by the intraoperative mechanical cardiopulmonary support strategy used. This surgery was historically done either on cardiopulmonary bypass (CPB) or off pump. Recently, there has been increased interest in intraoperative support with veno-arterial (VA) or veno-venous (VV) extracorporeal membrane oxygenation (ECMO). However, there is a lack of consensus on the relative risks, benefits and indications for each intraoperative support strategy.

AREAS COVERED

This review includes information from cohort studies, case-control studies, and case series that compare morbidity and/or mortality of two or more intraoperative cardiopulmonary support strategies during lung transplantation.

EXPERT OPINION

The optimal strategy for intraoperative cardiopulmonary support during lung transplantation remains an area of debate. Current data suggest that off pump is associated with better outcomes and could be considered whenever feasible. ECMO is generally associated with preferable outcomes to CPB, but the data supporting this association is not robust. Interestingly, whether CPB is unplanned or prolonged might influence outcomes more than the use of CPB itself. These observations can help guide surgical teams in their approach for intraoperative mechanical support strategy during lung transplantation and should serve as the basis for further investigations.

Single versus double lung transplantation for fibrotic disease-systematic review

Background

Lung transplantation has long been the accepted therapy for end-stage pulmonary fibrotic disease. Presently, there is an ongoing debate over whether single or bilateral transplantation is the most appropriate treatment for end-stage disease, with a paucity of high-quality evidence comparing the two approaches head-to-head.

Methods

This review was performed in accordance with PRISMA recommendations and guidance. Searches were performed on PubMed Central, Scopus and Medline from dates of database inception to September 2019. For the assessed papers, data was extracted from the reviewed text, tables and figures, by two independent authors. Estimated survival was analyzed using the Kaplan-Meier method for studies where time-to-event data was provided.

Results

Overall, 4,212 unique records were identified from the literature search. Following initial screening and the addition of reference list findings, 83 full-text articles were assessed for eligibility, of which 17 were included in the final analysis, with a total of 5,601 patients. Kaplan-Meier survival analysis illustrated improved survival in patients receiving bilateral lung transplantation (BLTx) than in those receiving unilateral transplantation for idiopathic pulmonary fibrosis at all time intervals, with aggregated survival for BLTx at 57%, 35.3% and 24% at 5-, 10- and 15-year follow-up, respectively. Survival rates for SLTx were 50%, 27.8% and 13.9%, respectively.

Conclusions

Whilst a number of studies present conflicting results with respect to short-term transplantation outcomes, BLTx confers improved long-term survival over SLTx, with large-scale registries supporting findings from single- and multi-center studies. Through an aggregation of published survival data, this meta-analysis identified improved survival in patients receiving BLTx versus SLTx at all time intervals.

Increased activated regulatory T cells proportion correlate with the severity of idiopathic pulmonary fibrosis

Background

Regulatory T cells (Tregs) are crucial in maintaining immune tolerance and immune homeostasis, but their role in idiopathic pulmonary fibrosis (IPF) is unclear. This study was designed to explore the role of Tregs in IPF.

Methods

Percentages of Tregs and their subpopulations in peripheral blood (PB) and bronchoalveolar lavage (BAL) samples were determined by flow cytometry in 29 patients with IPF, 19 patients with primary Sjögren’s syndrome-related interstitial pneumonia (pSS-IP), and 23 healthy controls (HCs).

Results

In peripheral blood, no difference was found in CD4⁺CD25⁺Foxp3⁺ Treg percentages among patients with IPF, pSS-IP, or HCs. However, activated Treg (aTreg) fractions among CD4⁺ T cells increased significantly in IPF compared with pSS-IP or HCs. Being consistent with the result from the PB, aTreg fractions among CD4⁺ T cells in IPF also increased significantly compared with pSS-IP or HCs, accompanied by increased fraction III compared with HCs in BAL. IPF patients had lower levels of resting Tregs (rTregs) from the thymus than did HCs, whereas aTreg levels originating from the thymus did not significantly differ from HCs. Both rTregs and aTregs proliferated in IPF, with aTregs being more proliferative than rTregs. Both rTregs and aTregs significantly inhibited proliferation of CD4⁺ T lymphocytes in vitro. The percentage of aTregs was correlated negatively with predicted diffusing capacity values for carbon monoxide and positively with GAP index in IPF.

Conclusions

Our study showed the imbalance between subpopulations of Tregs in IPF. Increased aTregs proportion in the peripheral blood correlated inversely with disease severity.

Functional improvement in patients with idiopathic pulmonary fibrosis undergoing single lung transplantation

Objective:

To evaluate the changes in lung function in the first year after single lung transplantation in patients with idiopathic pulmonary fibrosis (IPF).

Methods:

We retrospectively evaluated patients with IPF who underwent single lung transplantation between January of 2006 and December of 2012, reviewing the changes in the lung function occurring during the first year after the procedure.

Results:

Of the 218 patients undergoing lung transplantation during the study period, 79 (36.2%) had IPF. Of those 79 patients, 24 (30%) died, and 11 (14%) did not undergo spirometry at the end of the first year. Of the 44 patients included in the study, 29 (66%) were men. The mean age of the patients was 57 years. Before transplantation, mean FVC, FEV₁, and FEV₁/FVC ratio were 1.78 L (50% of predicted), 1.48 L (52% of predicted), and 83%, respectively. In the first month after transplantation, there was a mean increase of 12% in FVC (400 mL) and FEV₁ (350 mL). In the third month after transplantation, there were additional increases, of 5% (170 mL) in FVC and 1% (50 mL) in FEV₁. At the end of the first year, the functional improvement persisted, with a mean gain of 19% (620 mL) in FVC and 16% (430 mL) in FEV₁.

Conclusions:

Single lung transplantation in IPF patients who survive for at least one year provides significant and progressive benefits in lung function during the first year. This procedure is an important therapeutic alternative in the management of IPF.

Lung transplantation in idiopathic pulmonary fibrosis: a systematic review of the literature

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a distinct form of interstitial pneumonia with unknown origin and poor prognosis. Current pharmacologic treatments are limited and lung transplantation is a viable option for appropriate patients. The aim of this review was to summarize lung transplantation survival in IPF patients overall, between single (SLT) vs. bilateral lung transplantation (BLT), pre- and post Lung Allocation Score (LAS), and summarize wait-list survival.

METHODS

A systematic review of English-language studies published in Medline or Embase between 1990 and 2013 was performed. Eligible studies were those of observational design reporting survival post-lung transplantation or while on the wait list among IPF patients.

RESULTS

Median survival post-transplantation among IPF patients is estimated at 4.5 years. From ISHLT and OPTN data, one year survival ranged from 75% - 81%; 3-year: 59% - 64%; and 5-year: 47% - 53%. Post-transplant survival is lower for IPF vs. other underlying pre-transplant diagnoses. The proportion of IPF patients receiving BLT has steadily increased over the last decade and a half. Unadjusted analyses suggest improved long-term survival for BLT vs. SLT; after adjustment for patient characteristics, the differences tend to disappear. IPF patients account for the largest proportion of patients on the wait list and while wait list time has decreased, the number of transplants for IPF patients has increased over time. OPTN data show that wait list mortality is higher for IPF patients vs. other diagnoses. The proportion of IPF patients who died while awaiting transplantation ranged from 14% to 67%. While later transplant year was associated with increased survival, no significant differences were noted pre vs. post LAS implementation; however a high LAS vs low LAS was associated with decreased one-year survival.

CONCLUSIONS

IPF accounts for the largest proportion of patients awaiting lung transplants, and IPF is associated with higher wait-list and post-transplant mortality vs. other diagnoses. Improved BLT vs. SLT survival may be the result of selection bias. Survival pre- vs. post LAS appears to be similar except for IPF patients with high LAS, who have lower survival compared to pre-LAS. Data on post-transplant morbidity outcomes are sparse.

[Advances in respiratory health 2010: Techniques and Transplantation Section]

Five articles and an editorial on interventional pneumology were published in Archivos de Bronconeumología. Two of these articles deal with bronchoscopy, one with lung biopsy with cryoprobes, one with thermoplasty in asthma and the last with tracheobronchomalacia. We also review several publications in international journals, with special emphasis on endobronchial ultrasound. Four original articles on idiopathic pulmonary fibrosis were published in Archivos de Bronconeumología: one special article comparing two treatments and a Cochrane systematic review on the efficacy of non-steroidal drugs in this disease. Finally, we highlight studies in lung transplantation, consisting of 14 publications from different continents and with highly diverse contents: one editorial, one letter to the editor, one procedures manual and nine international publications on donor characteristics, various types of complications, experimental results in the field of preservation, and the casuistics obtained in distinct diseases in which transplantation is an option.

Lung transplantation in telomerase mutation carriers with pulmonary fibrosis

Lung transplantation is the only intervention that prolongs survival in idiopathic pulmonary fibrosis (IPF). Telomerase mutations are the most common identifiable genetic cause of IPF, and at times, the telomere defect manifests in extrapulmonary disease such as bone marrow failure. The relevance of this genetic diagnosis for lung transplant management has not been examined.

We gathered an international series of telomerase mutation carriers who underwent lung transplant in the USA, Australia and Sweden.

The median age at transplant was 52 years. Seven recipients are alive with a median follow-up of 1.9 years (range 6 months to 9 years); one died at 10 months. The most common complications were haematological, with recipients requiring platelet transfusion support (88%) and adjustment of immunosuppressives (100%). Four recipients (50%) required dialysis for tubular injury and calcineurin inhibitor toxicity. These complications occurred at significantly higher rates relative to historic series (p<0.0001).

Our observations support the feasibility of lung transplantation in telomerase mutation carriers; however, severe post-transplant complications reflecting the syndromic nature of their disease appear to occur at higher rates. While these findings need to be expanded to other cohorts, caution should be exercised when approaching the transplant evaluation and management of this subset of pulmonary fibrosis patients.

Telomerase mutation carriers with IPF may be prone to complications from their underlying telomere syndrome after LTxhttp://ow.ly/wmy6P

Comorbidities impacting on prognosis after lung transplant

The aim of this review is to give an overview of the clinical circumstances presenting before lung transplant that may have negative repercussions on the long and short-term prognosis of the transplant. Methods for screening and diagnosis of common comorbidities with negative impact on the prognosis of the transplant are proposed, both for pulmonary and extrapulmonary diseases, and measures aimed at correcting these factors are discussed. Coordination and information exchange between referral centers and transplant centers would allow these comorbidities to be detected and corrected, with the aim of minimizing the risks and improving the life expectancy of transplant receivers.

Lung transplantation for interstitial lung disease

For selected parenchymal lung disease patients who fail to respond to medical therapy and demonstrate declines in function that place them at increased risk for mortality, lung transplantation should be considered. Lung transplantation remains a complex medical intervention that requires a dedicated recipient and medical team. Despite the challenges, lung transplantation affords appropriate patients a reasonable chance at increased survival and improved quality of life. Lung transplantation remains an appropriate therapeutic option for selected patients with parenchymal lung disease.

Pirfenidone treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a discrete clinicopathologic entity defined by the presence of usual interstitial pneumonia on high-resolution CT scan and/or open lung biopsy and the absence of an alternate diagnosis or exposure explaining these findings. There are currently no FDA-approved therapies available to treat this disease, and the 5-year mortality is ∼80%. The pyridone derivative pirfenidone has been studied extensively as a possible therapeutic agent for use in this deadly disease. This review will present the unique clinical features and management issues encountered by physicians caring for IPF patients, including the poor response to conventional therapy. The biochemistry and preclinical efficacy of pirfenidone will be discussed along with a comprehensive review of the clinical efficacy, safety, and side effects and patient-centered foci such as quality of life and tolerability. It is hoped that this information will lend insight into the complex issues surrounding the use of pirfenidone in IPF and lead to further investigation of this agent as a possible therapy in this devastating disease.