The impact of time from ILD diagnosis to referral to the transplant center on the probability of inclusion in the transplant waiting list.

BACKGROUND: Lung transplant is a therapeutic option for patients with progressive interstitial lung disease (ILD). OBJECTIVES: The objective of this study was to determine whether time from ILD diagnosis to referral to a transplant center influences the probability of being included in the transplant waiting list. METHODS: We performed a retrospective cohort study including all ILD patients evaluated as lung transplantation (LT) candidates at a lung transplant center between 01/01/2017 and 31/12/2022. The primary endpoint was the probability of being included in the lung transplant waiting list according to the time elapsed from diagnosis to referral to the transplant center. RESULTS: A total of 843 lung transplant requests were received, of which 367 (43.5%) were associated with ILD. Thirteen patients were excluded because they did not attend the first visit, whereas another 11 were excluded because some information was missing. As a result, our final sample was composed of 343 patients. The median time from diagnosis to referral was 29.4 (10.9 - 61.1) months. The overall probability of inclusion in the waiting list was 29.7%. By time from diagnosis to referral, the probability of inclusion in the waiting list was 48.1% for the patients referred 〈 6 months from diagnosis; 27.5% for patients referred 6 to 24 months from diagnosis; and 25.8% for patients referred 〉 24 months from diagnosis (p = 0.007). CONCLUSIONS: Early referral to a lung transplant center seemed to increase the probability of being included in the lung transplant waiting list. Further research is needed in this topic.

Inflammasome-Related Genetic Polymorphisms as Severity Biomarkers of COVID-19.

The most critical forms of coronavirus disease 2019 (COVID-19) are associated with excessive activation of the inflammasome. Despite the COVID-19 impact on public health, we still do not fully understand the mechanisms by which the inflammatory response influences disease prognosis. Accordingly, we aimed to elucidate the role of polymorphisms in the key genes of the formation and signaling of the inflammasome as biomarkers of COVID-19 severity. For this purpose, a large and well-defined cohort of 377 COVID-19 patients with mild (n = 72), moderate (n = 84), severe (n = 100), and critical (n = 121) infections were included. A total of 24 polymorphisms located in inflammasome-related genes (NLRP3, NLRC4, NLRP1, CARD8, CASP1, IL1B, IL18, NFKB1, ATG16L1, and MIF) were genotyped in all of the patients and in the 192 healthy controls (HCs) (who were without COVID-19 at the time of and before the study) by RT-qPCR. Our results showed that patients with mild, moderate, severe, and critical COVID-19 presented similar allelic and genotypic distribution in all the variants studied. No statistically significant differences in the haplotypic distribution of NLRP3, NLRC4, NLRP1, CARD8, CASP1, IL1B, and ATG16L1 were observed between COVID-19 patients, who were stratified by disease severity. Each stratified group of patients presented a similar genetic distribution to the HCs. In conclusion, our results suggest that the inflammasome polymorphisms studied are not associated with the worsening of COVID-19.

Impact of the New Definition of Pulmonary Hypertension on the Prevalence of Primary Graft Dysfunction in Lung Transplant Recipients.

BACKGROUND & AIM: Pulmonary hypertension (PH) secondary to lung disease (Group-3 PH) is the second leading cause of PH. The role of PH as a risk factor for primary graft dysfunction (PGD) following lung transplant (LT) is controversial. OBJECTIVE: To assess the impact that the new definition of PH had on the prevalence of PH in patients with advanced lung disease-candidate for LT, and its association with the occurrence of PGD. METHOD: A retrospective study was performed in all patients undergoing cardiac catheterisation referred for consideration as candidates to LT in a centre between 1 January 2017 and 31 December 2022. The baseline and haemodynamic characteristics of patients were analysed, along with the occurrence of PGD and post-transplant course in those who ultimately underwent transplantation. RESULTS: A total of 396 patients were included. Based on the new 2022 European Society of Cardiology/European Respiratory Society definitions, as many as 70.7% of patients met PH criteria. Since the introduction of the 2022 definition, a significant reduction was observed in the frequency of severe Group-3 PH (41.1% vs 10.3%; p<0.001), with respect to the 2015 definition. As many as 236 patients underwent transplantation. None of the variables associated with PH was identified as a risk factor for PGD. CONCLUSION: The new classification did not have any impact on the prevalence of PGD after transplantation. These results exclude that any significant differences exist in the baseline characteristics or post-transplant course of patients with Group-3 PH vs unclassified PH.

DQA1 Eplet Mismatch Load As an Independent Risk Factor of CLAD After Lung Transplantation.

Lung transplantation remains the treatment of choice for end-stage lung diseases, and recipient selection is currently based on clinical urgency, ABO compatibility, and donor size. The risk of allosensitization is classically based on HLA mismatch, but eplet mismatch load is increasingly seen to be important in long-term outcomes in solid organ transplantation. Chronic lung allograft dysfunction (CLAD) is relatively common and relevant, affecting almost 50% of patients 5 y after transplantation and being the first cause of death from the first year after transplantation. The overall class-II eplet mismatch load has been associated with CLAD development. Methods: Based on clinical data, 240 lung transplant recipients were eligible for CLAD, and HLA and eplet mismatch was analyzed using the HLAMatchmaker 3.1 software. Results: A total of 92 (38.3%) lung transplant recipients developed CLAD. The time free-of-CLAD was significantly decreased in patients with presence of DQA1 eplet mismatches (P = 0.015). Furthermore, when other previously described CLAD risk factors were studied in a multivariate analysis, the presence of DQA1 eplet mismatches was found to be independently associated with the early onset of CLAD. Conclusions: The concept of epitope load has arisen as a new tool to better define donor-recipient immunologic compatibility. The presence of DQA1 eplet mismatches potentially would increase the likelihood of developing CLAD.

Bronchial Stenosis After Lung Transplantation From cDCD Donors Using Simultaneous Abdominal Normothermic Regional Perfusion: A Single-center Experience.

BACKGROUND: Controlled donation after circulatory death (cDCD) has increased the number of lung donors significantly. The use of abdominal normothermic regional perfusion (A-NRP) during organ procurement is a common practice in some centers due to its benefits on abdominal grafts. This study aimed to assess whether the use of A-NRP in cDCD increases the frequency of bronchial stenosis in lung transplant (LT) recipients. METHODS: A single-center, retrospective study including all LTs was performed between January 1, 2015, and August 30, 2022. Airway stenosis was defined as a stricture that leads to clinical/functional worsening requiring the use of invasive monitoring and therapeutic procedures. RESULTS: A total of 308 LT recipients were included in the study. Seventy-six LT recipients (24.7%) received lungs from cDCD donors using A-NRP during organ procurement. Forty-seven LT recipients (15.3%) developed airway stenosis, with no differences between lung recipients with grafts from cDCD (17.2%) and donation after brain death donors (13.3%; P = 0.278). A total of 48.9% of recipients showed signs of acute airway ischemia on control bronchoscopy at 2 to 3 wk posttransplant. Acute ischemia was an independent risk factor for airway stenosis development (odds ratio = 2.523 [1.311-4.855], P = 0.006). The median number of bronchoscopies per patient was 5 (2-9), and 25% of patients needed >8 dilatations. Twenty-three patients underwent endobronchial stenting (50.0%) and each patient needed a median of 1 (1-2) stent. CONCLUSIONS: Incidence of airway stenosis is not increased in LT recipients with grafts obtained from cDCD donors using A-NRP.

Early Postoperative Outcomes of Lung Transplant Recipients With Abdominal Adverse Events.

INTRODUCTION: Patients undergoing lung transplantation (LT) are at high risk of developing serious abdominal complications, which can lead to higher rates of morbidity and mortality. The aim of this study was to investigate the incidence and spectrum of these complications when they develop during the first 30 days after LT, as well as their possible association with possible risk factors. METHODS: A retrospective study of 552 patients undergoing LT between 01/02/2006 and 06/03/2021 was carried out. A descriptive and analytical evaluation of the patients who experienced complications and those who did not was performed comparatively. Data related to patient characteristics and the lung transplantation procedure were collected. RESULTS: Overall, 8.2% of patients developed severe abdominal complications during the first 30 days; paralytic ileus was the most frequent (31.1%), closely followed by visceral perforation (26.7%). The percentage of patients who required an invasive procedure to manage post-transplant complications was 57.8%. Surgical intervention was required in 39.8%. The variables that showed a significant relationship with the development of severe short-term abdominal complications in the univariate analysis were the time of surgery, the use of ECMO/ ECC and red blood cell transfusion during or after surgery. In the multivariate study, however, only duration of surgery remained significant (p=0.03). CONCLUSION: The incidence of severe short-term abdominal complications after LT period was 8%. The commonest complications were paralytic ileus and intestinal perforation. Most patients did not require surgery. The only risk factor found associated with these complications was the duration of the surgical intervention.

Early onset of azithromycin to prevent CLAD in lung transplantation: Promising results of a retrospective single centre experience.

INTRODUCTION: Azithromycin (AZI) may be an effective immune modulator in lung transplant (LT) recipients, and can decrease chronic lung allograft dysfunction (CLAD) rates, the leading cause of mortality after the 1st year post-LT. The aim of the study is to assess the effect of AZI initiation and its timing on the incidence and severity of CLAD in LT recipients. METHODS: Single-center retrospective study, including LT recipients from 01/01/2011 to 30/06/2020. Four groups were established: those who started AZI at the 3rd week post-LT (group A), those who received AZI later than the 3rd week post-LT and had preserved FEV1 (B), those who did not receive AZI (C) and those who started AZI due to a decline in FEV1 (D). The dosage of AZI prescribed was 250 mg three times per week. CLAD was defined and graduated according to the 2019 ISHLT criteria. RESULTS: We included 358 LT recipients: 139 (38.83%) were in group A, 94 (26.25%) in group B, 91 (25.42%) in group C, and 34 (9.50%) in group D. Group A experienced the lowest CLAD incidence and severity at 1 (p = .01), 3 (p < .001), and 5 years post-LT, followed by Group B. Groups C and D experienced a higher incidence and severity of CLAD (p = .015). Initiation of AZI prior to FEV1 decline (Groups A and B) proved to be protective against CLAD after adjusting for differences between the treatment groups. CONCLUSIONS: Early initiation of AZI in LT recipients could have a role in decreasing the incidence and severity of CLAD. In addition, as long as FEV1 is preserved, initiating AZI at any time could also be useful to prevent the incidence of CLAD and reduce its severity.

Lung transplantation for emphysema: only emphysema or something else?

Background: Some studies have reviewed lung explants histology to determine the frequency of pretransplant non-identified neoplasms or explore its diagnostic correlation with a previous diagnosis of interstitial lung disease (ILD). This study aims to review the histopathology of explants from patients who underwent lung transplantation (LT). Methods: A retrospective, single-center study that included patients who underwent LT for emphysema between 01 January 2011 and 31 October 2021. The control group was composed of patients with lung cancer who underwent a lung resection between 01 November 2011 and 31 December 2019 and had a previous diagnosis of chronic obstructive pulmonary disease (COPD) prior to lung resection surgery. A systematic review was performed of histological findings to compare the frequency of additional histological diagnoses. Results: The study sample included 160 patients (43.8%) who received a lung transplant for emphysema and 205 patients with COPD and lung cancer treated surgically. Although the patients in the cancer group were significantly older and had more comorbidities and higher cumulative tobacco consumption, transplant recipients received an additional significative histologic diagnosis more frequently (58.1% vs. 12.7%; P<0.001) including ILD, pneumoconiosis and others. Conclusions: Significant additional histological findings were more frequent in the group of lung transplant recipients with emphysema. Notably, these findings were not explained by tobacco use, and they were significantly more frequent in transplant recipients than in patients with a previous diagnosis of COPD and higher cumulative tobacco consumption but with a better respiratory functional status.

Lack of concordance between the different exercise test measures used in the risk stratification of patients with pulmonary arterial hypertension.

In pulmonary arterial hypertension (PAH) patients it is essential to perform a prognostic assessment to optimize the treatment. The aim of this study is to evaluate the risk stratification concordance assessed with different exercise test variables in a cohort of PAH patients. A retrospective analysis was performed using patient data registered in the PAH unit. Only those patients in whom the mean time elapsed between the 6-min walking test (6MWT) and the cardiopulmonary exercise test (CPET) was a maximum of 6 months were selected. A total of 140 records from 40 patients were finally analyzed. When it came to assessing the concordance between the two exercise tests in the guidelines (CPET and 6MWT), up to 84.3% of the records did not coincide in terms of the risk stratification. Exclusively considering the CPET parameters, most of the records (75%) failed to include all three variables in the same risk category. When analyzing the VO2 alone, up to 40.7% of the tests yielded different risk classifications depending on whether the parameter was expressed. In conclusion, there is a low concordance between the two proposed exercise tests. These results should be a call for reflection on whether the cut-off points set for the exercise tests proposed for the current risk stratification are adequate to achieve a correct risk stratification or whether they require an appropriate revision.

Prevalence of Neuropathic Component in Post-COVID Pain Symptoms in Previously Hospitalized COVID-19 Survivors.

Objectives: To investigate the prevalence of neuropathic pain symptoms and to analyze the correlation between neuropathic symptoms with pain-related, psychological, and cognitive variables in COVID-19 survivors exhibiting "de novo" post-COVID pain. Methods: Seventy-seven (n = 77) previously hospitalized COVID-19 survivors presenting with post-COVID pain completed demographic (such as age, height, and weight), pain-related (the duration and intensity of pain), psychological (depressive/anxiety levels), and cognitive (catastrophizing and kinesiophobia) variables. The Self-Report Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS) questionnaire was also assessed. After conducting multivariable correlation analyses, a stepwise multiple linear regression model was performed to identify S-LANSS predictors. Results: Participants were assessed a mean of 6.0 (SD 0.8) months after hospital discharge. Nineteen (24.6%) exhibited neuropathic pain symptoms (S-LANSS score≥12 points). The S-LANSS score was positively associated with the duration of post-COVID pain (r: 0.262), anxiety levels (r: 0.275), and kinesiophobia level (r: 0.291) (all, P < 0.05). The stepwise regression analysis revealed that 12.8% of the S-LANSS variance was just explained by kinesiophobia. Conclusion: This study found that almost 25% of previously hospitalized COVID-19 survivors with "de novo" post-COVID pain reported a neuropathic pain component. The presence of neuropathic pain symptomatology was associated with more anxiety and kinesiophobia, but only kinesiophobia level was significantly associated explaining 12.8% of the variance of the S-LANSS score.

Exacerbation of chronic renal failure because of inhaled tobramycin in a lung transplant patient.

61-year-old man, with a history of years of unknown etiology bronchiectasis, with chronic bronchial infection by Burkholderia multivorans, who received treatment with a double lung transplant on 08/20/2020. Persistent positive cultures of Burkholderia multivorans after transplant in respiratory samples was observed, and treatment with inhaled tobramycin 300 mg/12 hours was started. One month after treatment, a significant worsening of renal function was observed, which was already altered, and toxic levels of tobramycin were measured in blood samples 12 hours after the last inhaled administration. After stopping treatment, kidney function returned to its baseline values.