T-cell recovery and evidence of persistent immune activation 12 months after severe COVID-19.

BACKGROUND: T-cell lymphopenia and functional impairment is a hallmark of severe acute coronavirus disease 2019 (COVID-19). How T-cell numbers and function evolve at later timepoints after clinical recovery remains poorly investigated. METHODS: We prospectively enrolled and longitudinally sampled 173 individuals with asymptomatic to critical COVID-19 and analyzed phenotypic and functional characteristics of T cells using flow cytometry, 40-parameter mass cytometry, targeted proteomics, and functional assays. RESULTS: The extensive T-cell lymphopenia observed particularly in patients with severe COVID-19 during acute infection had recovered 6 months after infection, which was accompanied by a normalization of functional T-cell responses to common viral antigens. We detected persisting CD4+ and CD8+ T-cell activation up to 12 months after infection, in patients with mild and severe COVID-19, as measured by increased HLA-DR and CD38 expression on these cells. Persistent T-cell activation after COVID-19 was independent of administration of a COVID-19 vaccine post-infection. Furthermore, we identified a subgroup of patients with severe COVID-19 that presented with persistently low CD8+ T-cell counts at follow-up and exhibited a distinct phenotype during acute infection consisting of a dysfunctional T-cell response and signs of excessive pro-inflammatory cytokine production. CONCLUSION: Our study suggests that T-cell numbers and function recover in most patients after COVID-19. However, we find evidence of persistent T-cell activation up to 12 months after infection and describe a subgroup of severe COVID-19 patients with persistently low CD8+ T-cell counts exhibiting a dysregulated immune response during acute infection.

Autoantibodies in COVID-19 correlate with antiviral humoral responses and distinct immune signatures.

BACKGROUND: Several autoimmune features occur during coronavirus disease 2019 (COVID-19), with possible implications for disease course, immunity, and autoimmune pathology. In this study, we longitudinally screened for clinically relevant systemic autoantibodies to assess their prevalence, temporal trajectory, and association with immunity, comorbidities, and severity of COVID-19. METHODS: We performed highly sensitive indirect immunofluorescence assays to detect antinuclear antibodies (ANA) and antineutrophil cytoplasmic antibodies (ANCA), along with serum proteomics and virome-wide serological profiling in a multicentric cohort of 175 COVID-19 patients followed up to 1 year after infection, eleven vaccinated individuals, and 41 unexposed controls. RESULTS: Compared with healthy controls, similar prevalence and patterns of ANA were present in patients during acute COVID-19 and recovery. However, the paired analysis revealed a subgroup of patients with transient presence of certain ANA patterns during acute COVID-19. Furthermore, patients with severe COVID-19 exhibited a high prevalence of ANCA during acute disease. These autoantibodies were quantitatively associated with higher SARS-CoV-2-specific antibody titers in COVID-19 patients and in vaccinated individuals, thus linking autoantibody production to increased antigen-specific humoral responses. Notably, the qualitative breadth of antibodies cross-reactive with other coronaviruses was comparable in ANA-positive and ANA-negative individuals during acute COVID-19. In autoantibody-positive patients, multiparametric characterization demonstrated an inflammatory signature during acute COVID-19 and alterations of the B-cell compartment after recovery. CONCLUSION: Highly sensitive indirect immunofluorescence assays revealed transient autoantibody production during acute SARS-CoV-2 infection, while the presence of autoantibodies in COVID-19 patients correlated with increased antiviral humoral immune responses and inflammatory immune signatures.

Systemic and mucosal antibody responses specific to SARS-CoV-2 during mild versus severe COVID-19.

BACKGROUND: Whereas severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibody tests are increasingly being used to estimate the prevalence of SARS-CoV-2 infection, the determinants of these antibody responses remain unclear. OBJECTIVES: Our aim was to evaluate systemic and mucosal antibody responses toward SARS-CoV-2 in mild versus severe coronavirus disease 2019 (COVID-19) cases. METHODS: Using immunoassays specific for SARS-CoV-2 spike proteins, we determined SARS-CoV-2-specific IgA and IgG in sera and mucosal fluids of 2 cohorts, including SARS-CoV-2 PCR-positive patients (n = 64) and PCR-positive and PCR-negtive health care workers (n = 109). RESULTS: SARS-CoV-2-specific serum IgA titers in patients with mild COVID-19 were often transiently positive, whereas serum IgG titers remained negative or became positive 12 to 14 days after symptom onset. Conversely, patients with severe COVID-19 showed a highly significant increase of SARS-CoV-2-specific serum IgA and IgG titers after symptom onset. Very high titers of SARS-CoV-2-specific serum IgA were correlated with severe acute respiratory distress syndrome. Interestingly, some health care workers with negative SARS-CoV-2-specific serum antibody titers showed SARS-CoV-2-specific IgA in mucosal fluids with virus-neutralizing capacity in some cases. SARS-CoV-2-specific IgA titers in nasal fluids were inversely correlated with age. CONCLUSIONS: Systemic antibody production against SARS-CoV-2 develops mainly in patients with severe COVID-19, with very high IgA titers seen in patients with severe acute respiratory distress syndrome, whereas mild disease may be associated with transient production of SARS-CoV-2-specific antibodies but may stimulate mucosal SARS-CoV-2-specific IgA secretion.

Profound dysregulation of T cell homeostasis and function in patients with severe COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and shows a broad clinical presentation ranging from asymptomatic infection to fatal disease. A very prominent feature associated with severe COVID-19 is T cell lymphopenia. However, homeostatic and functional properties of T cells are ill-defined in COVID-19. METHODS: We prospectively enrolled individuals with mild and severe COVID-19 into our multicenter cohort and performed a cross-sectional analysis of phenotypic and functional characteristics of T cells using 40-parameter mass cytometry, flow cytometry, targeted proteomics, and functional assays. RESULTS: Compared with mild disease, we observed strong perturbations of peripheral T cell homeostasis and function in severe COVID-19. Individuals with severe COVID-19 showed T cell lymphopenia and redistribution of T cell populations, including loss of naïve T cells, skewing toward CD4+ T follicular helper cells and cytotoxic CD4+ T cells, and expansion of activated and exhausted T cells. Extensive T cell apoptosis was particularly evident with severe disease and T cell lymphopenia, which in turn was accompanied by impaired T cell responses to several common viral antigens. Patients with severe disease showed elevated interleukin-7 and increased T cell proliferation. Furthermore, patients sampled at late time points after symptom onset had higher T cell counts and improved antiviral T cell responses. CONCLUSION: Our study suggests that severe COVID-19 is characterized by extensive T cell dysfunction and T cell apoptosis, which is associated with signs of homeostatic T cell proliferation and T cell recovery.

Bronchoalveolar lavage cytokines are of minor value to diagnose complications following lung transplantation.

Early diagnosis and treatment of acute cellular rejection (ACR) may improve long-term outcome for lung transplant recipients (LTRs). Cytokines have become valuable diagnostic tools in many medical fields. The role of bronchoalveolar lavage (BAL) cytokines is of unknown value to diagnose ACR and distinguish rejection from infection. We hypothesized that distinct cytokine patterns obtained by surveillance bronchoscopies during the first year after transplantation are associated with ACR and microbiologic findings. We retrospectively analyzed data from 319 patients undergoing lung transplantation at University Hospital Zurich from 1998 to 2016. We compared levels of IL-6, IL-8, IFN-γ and TNF-α in 747 BAL samples with transbronchial biopsies (TBB) and microbiologic results from surveillance bronchoscopies. We aimed to define reference values that would allow distinction between four specific groups "ACR", "infection", "combined ACR and infection" and "no pathologic process". No definitive pattern was identified. Given the overlap between groups, these four cytokines are not suitable diagnostic markers for ACR or infection after lung transplantation.

Pulmonary hypertension is not a risk factor for grade 3 primary graft dysfunction after lung transplantation.

Grade 3 primary graft dysfunction (PGD3) represents the most important risk factor for patient mortality during the first year after lung transplantation (LTX). We investigated whether pretransplant pulmonary hypertension (PH) is a risk factor for the development of PGD3. This retrospective, single-center cohort study included 96 candidates undergoing right heart catheterization (RHC) prior to being listed for LTX between March 2000 and October 2015. Based on their mean pulmonary artery pressure (mPAP) levels, the patients were classified into 3 groups: (1) <25 mm Hg, (2) 25-34 mm Hg and (3) ≥35 mm Hg. Forty-seven patients were classified in group 1, 31 in group 2, and 18 in group 3. Fifteen recipients (16%, 95%-CI 8-23) developed PGD3. In the univariate analysis, the diagnosis of interstitial lung disease (ILD) compared to COPD (OR: 7.06, P = .005), blood transfusion >1000 mL during surgery (OR: 5.25, P = .005), the need for intra-operative cardio-pulmonary bypass (CPB) or extra-corporeal membrane oxygenation (ECMO) (OR: 4, P = .027), mPAP (OR 1.06, P = .007) and serum high density lipoprotein-cholesterol (HDL-C) (OR 0.09, P = .005) were associated with PGD3. In the multivariable logistic regression analysis, only HDL-C (OR 0.10, P = .016) was associated with PGD3 based on our single-center cohort data analysis.

Aquaporin 1 controls the functional phenotype of pulmonary smooth muscle cells in hypoxia-induced pulmonary hypertension.

Vascular remodelling in hypoxia-induced pulmonary hypertension (PH) is driven by excessive proliferation and migration of endothelial and smooth muscle cells. The expression of aquaporin 1 (AQP1), an integral membrane water channel protein involved in the control of these processes, is tightly regulated by oxygen levels. The role of AQP1 in the pathogenesis of PH, however, has not been directly addressed so far. This study was designed to characterize expression and function of AQP1 in pulmonary vascular cells from human arteries and in the mouse model of hypoxia-induced PH. Exposure of human pulmonary vascular cells to hypoxia significantly induced the expression of AQP1. Similarly, levels of AQP1 were found to be upregulated in lungs of mice with hypoxia-induced PH. The functional role of AQP1 was further tested in human pulmonary artery smooth muscle cells demonstrating that depletion of AQP1 reduced proliferation, the migratory potential, and, conversely, increased apoptosis of these cells. This effect was associated with higher expression of the tumour suppressor gene p53. Using the mouse model of hypoxia-induced PH, application of GapmeR inhibitors targeting AQP1 abated the hypoxia-induced upregulation of AQP1 and, of note, reversed PH by decreasing both right ventricular pressure and hypertrophy back to the levels of control mice. Our data suggest an important functional role of AQP1 in the pathobiology of hypoxia-induced PH. These results offer novel insights in our pathogenetic understanding of the disease and propose AQP1 as potential therapeutic in vivo target.

Plasma and bronchoalveolar lavage samples in acute lung allograft rejection: the potential role of cytokines as diagnostic markers.

The role of differential cytology patterns in peripheral blood and bronchoalveolar lavage samples is increasingly investigated as a potential adjunct to diagnose acute and chronic allograft dysfunction after lung transplantation. While these profiles might facilitate the diagnosis of acute cellular rejection, low sensitivity and specificity of these patterns limit direct translation in a clinical setting. In this context, the identification of other biomarkers is needed. This review article gives an overview of cytokine profiles of plasma and bronchoalveolar lavage samples during acute cellular rejection. The value of these cytokines in supporting the diagnosis of acute cellular rejection is discussed. Current findings on the topic are highlighted and experimental settings for future research projects are identified.

Low tissue levels of miR-125b predict malignancy in solitary fibrous tumors of the pleura.

BACKGROUND: Solitary fibrous tumors of the pleura (SFTP) are rare neoplasia of the chest. A subset of SFTP follows a malignant course, sometimes several years after complete resection. Traditional scoring systems based on clinical and histological features are poor predictors of biological behavior. This study aimed to investigate tumor-associated miRNAs expression as novel biomarkers to predict the clinical behavior of SFTP. METHODS: Formalin-fixed and paraffin-embedded SFTP tissues blocks from patients surgically resected between 1992 and 2013 at two tertiary care teaching hospitals were included. SFTP tumors were categorized as either malignant or benign variants according to the WHO classification. Following miRNAs levels were measured: let-7a, miR-16b, miR-17, miR-21, miR-31, miR-34a, miR-92a, miR-125a, miR-125b, miR-195-5b, miR-203a, and miR-223. Differential gene expressions which were calculated with the threshold cycle (Ct) method were compared among the two variants. RESULTS: Thirty-eight patients (40% male, mean age 62.2 (±10.9) years) were included. Expression levels of miR-125b showed a significant difference between benign compared to malignant variants (-3.08 ± 0.93 vs. -2.22 ± 1.36, p = 0.0068). Furthermore, lower levels of miR-125b were found to be associated with increased tumor size (p = 0.0414). Thus, downregulation of miR-125b indicates malignant transformation. All other investigated miRNAs were not associated with grading of SFTP. CONCLUSIONS: Our data suggest a potential role of miR-125b in the pathogenesis of tumor growth and malignant transformation of SFTP, respectively. Further studies have to address the potential use of miRNA-125b as a biomarker or therapeutic target in SFTP.

Lung transplant recipients on long-term extracorporeal photopheresis.

Extracorporeal photophoresis (ECP) is an increasingly used therapy to address chronic lung allograft dysfunction (CLAD) following lung transplantation. In 2008, we reported the first single-center experience showing that ECP not only reduces lung function decline in patients with bronchiolitis obliterans syndrome (BOS) but results in stabilization of patients with recurrent acute cellular rejection (ACR). In this study, the original cohort was followed up further 5 years. In addition, patients with CLAD were retrospectively classified according to recently published phenotypes. The current cohort included 21 of the original 24 patients, of which nine were initially treated for CLAD, 12 were initially treated for recurrent ACR. Our results show that survival of patients treated with ECP for CLAD was inferior to patients treated for recurrent ACR (66% vs. 82% survival rate). Long-term survivors in the CLAD subgroup were mostly classified as BOS 1 at time of ECP initiation. These long-term data show that patients started on ECP at early BOS stages have better long-term outcome. The subgroup of ECP patients with recurrent ACR has an overall superior survival. To assist prediction of therapy response, we agree with other authors that patients with CLAD should be aimed to be phenotyped and evaluated for an early treatment with ECP.

Exercise pulmonary haemodynamics predict outcome in patients with systemic sclerosis.

The aim of the present study was to investigate the prognostic value of exercise haemodynamics measured during right heart catheterisation (RHC) in patients with systemic sclerosis (SSc) referred for evaluation of pulmonary hypertension.SSc patients undergoing RHC at rest and during maximal supine incremental cycle exercise were grouped into resting precapillary pulmonary hypertension (PHrest) (mean pulmonary artery pressure (mPAP) ≥25 mmHg, pulmonary artery wedge pressure <15 mmHg), exercise-induced pulmonary hypertension (PHex) (mPAP ≥30 mmHg and mPAP/cardiac output >3 mmHg·L-1·min-1 at maximal exercise), and without pulmonary hypertension (PHnone). Patients' characteristics, haemodynamics and follow up data were compared between groups.72 SSc patients were followed for median (interquartile range) 33 (15-55) months. Mean (95% CI) survival without transplantation estimated by Kaplan-Meyer analysis was 4.4 (0.8-2.9) years in PHrest (n=17), 5.2 (4.4-6.1) years in PHex (n=28) and 9.5(8.4-10.6) years in PHnone (n=27; p<0.05 versus others). In Cox regression models, the exercise-induced increase in mPAP (hazard ratio (HR) 1.097, 95% CI 1.002-1.200) and the coefficient of pulmonary vascular distensibility alpha (HR 0.100, 95% CI 0.012-0.871) controlled for age, but not resting haemodynamics predicted transplant-free survival.Among SSc patients with normal mPAP at rest, an excessive increase in mPAP during exercise and an impaired vascular distensibility may indicate an early stage of pulmonary vasculopathy, associated with reduced survival similar to resting pulmonary hypertension patients.

Diagnostic value of plasma and bronchoalveolar lavage samples in acute lung allograft rejection: differential cytology.

Diagnosis of acute lung allograft rejection is currently based on transbronchial lung biopsies. Additional methods to detect acute allograft dysfunction derived from plasma and bronchoalveolar lavage samples might facilitate diagnosis and ultimately improve allograft survival. This review article gives an overview of the cell profiles of bronchoalveolar lavage and plasma samples during acute lung allograft rejection. The value of these cells and changes within the pattern of differential cytology to support the diagnosis of acute lung allograft rejection is discussed. Current findings on the topic are highlighted and trends for future research are identified.

Isolation of Stenotrophomonas maltophilia in asymptomatic lung transplant recipients: effects of treatment on eradication and outcome.

In this retrospective, single-center data analysis, we audited our clinical practice to treat Stenotrophomonas maltophilia in asymptomatic lung transplant recipients (LTRs). Eighteen LTRs with confirmed isolation of S. maltophilia were identified. Twelve of these LTRs have been treated with antibiotics, while 6 were managed without treatment. Treatment was based on antibiograms (trimethoprim/sulfamethoxazole [TMP/SMX] (8/12), levofloxacin (1/12), or both (3/12). Clearance (12/12 vs 6/6), eradication (10/12 vs 3/6, P=.27), and freedom from S. maltophilia recurrence (83%±11% vs 40%±22% after one year, log-rank P=.09) were not found to differ significantly between treated and untreated patients. None of the patient groups showed significant changes in lung function or biochemical variables. Creatinine levels at the end of the study period were found to be higher in treated patients compared to the untreated group (P=.049). De novo acquired TMP/SMX resistance in S. maltophilia strains was not observed. These results indicate no evidence that antibiotic treatment for S. maltophilia in asymptomatic LTRs alters lung function or the clinical outcome.

Prevalence of Anxiety and Depression in Pulmonary Hypertension and Changes during Therapy.

BACKGROUND: Pulmonary hypertension (PH) leads to reduced health-related quality of life (HRQoL). OBJECTIVE: To investigate the prevalence and course of anxiety and depression and their association with HRQoL, disease severity and survival in PH. METHODS: 131 PH patients (91 pulmonary arterial, 30 chronic thromboembolic, 10 due to lung disease; 84 female, 47 male) had repeated assessments with the Hospital Anxiety and Depression Scale (HADS), HRQoL, six-minute walk distance and WHO functional class during a mean course of 16 ± 12 months. RESULTS: Among the 49 incident and 82 prevalent PH patients, the HADS score was positive in 53%/21% (depression), 51%/24% (anxiety) and 63%/26% (total score) (all p < 0.05). The HADS score was improved at the second assessment in incident patients. The HADS score correlated with HRQoL at all consecutive assessments and with functional class until the third assessment, but not with baseline hemodynamics, age or gender. CONCLUSION: Mood disorders remain underdiagnosed in PH. The higher prevalence of anxiety/depression in incident versus prevalent patients and the improvement over time may indicate an amelioration of mood disorders after PH diagnosis and treatment.

Effect of nocturnal oxygen and acetazolamide on exercise performance in patients with pre-capillary pulmonary hypertension and sleep-disturbed breathing: randomized, double-blind, cross-over trial.

AIM: Sleep-disturbed breathing (SDB) is common in pre-capillary pulmonary hypertension (PH) and impairs daytime performance. In lack of proven effective treatments, we tested whether nocturnal oxygen therapy (NOT) or acetazolamide improve exercise performance and quality of life in patients with pre-capillary PH and SDB. METHODS: This was a randomized, placebo-controlled, double-blind, three period cross-over trial. Participants received NOT (3 L/min), acetazolamide tablets (2 × 250 mg), and sham-NOT/placebo tablets each during 1 week with 1-week washout between treatment periods. Twenty-three patients, 16 with pulmonary arterial PH, 7 with chronic thromboembolic PH, and with SDB defined as mean nocturnal oxygen saturation <90% or oxygen saturation dips >10 h(-1) with daytime PaO2 ≥7.3 kPa participated. Assessments at the end of the treatment periods included a 6 min walk distance (MWD), SF-36 quality of life, polysomnography, and echocardiography. RESULTS: Medians (quartiles) of the 6 MWD after NOT, acetazolamide, and placebo were 480 m (390;528), 440 m (368;468), and 454 m (367;510), respectively, mean differences: NOT vs. placebo +25 m (95% CI 3-46, P= 0.027), acetazolamide vs. placebo -9 m (-34-17, P = 0.223), and NOT vs. acetazolamide +33 (12-45, P < 0.001). SF-36 quality of life was similar with all treatments. Nocturnal oxygen saturation significantly improved with both NOT and acetazolamide. Right ventricular fractional area change was greater on NOT compared with placebo (P = 0.042) and acetazolamide (P = 0.027). CONCLUSIONS: In patients with pre-capillary PH and SDB on optimized pharmacological therapy, NOT improved the 6 MWD compared with placebo already after 1 week along with improvements in SDB and haemodynamics. CLINICALTRIALSGOV: NTC01427192.

Efficacy and Safety of Long-Term Imatinib Therapy for Pulmonary Arterial Hypertension.

BACKGROUND: Antiproliferative strategies have emerged as a potential therapeutic option for pulmonary arterial hypertension (PAH). OBJECTIVE: To evaluate the long-term efficacy and safety of imatinib. METHODS: This is an observational study of 15 patients with idiopathic PAH (n = 13) or PAH associated with connective tissue disease (n = 2) treated off-label with imatinib 400 mg daily. Pulmonary hypertension-specific therapy was established in all patients (triple therapy in 10, dual therapy in 3, and monotherapy in 2 patients). RESULTS: After 6 months, improvement in hemodynamics (p < 0.01), functional class (p = 0.035), and quality of life (p = 0.005) was observed. After a median follow-up of 37 months, there was a sustained improvement in functional class (p = 0.032), quality of life (p = 0.019), and echocardiographic parameters of right ventricular function (p < 0.05). Three patients (20%) presented with completely normal echocardiography, absent tricuspid regurgitation, and normal pro-brain natriuretic peptide levels, indicative of 'hemodynamic remission'. Of note, however, only 1 case was assessed by invasive hemodynamics. The overall 1- and 3-year survival was 100 and 90%, respectively. Two patients experienced a subdural hematoma (SDH), which in both cases resolved without sequelae. After careful consultation of the potential risks and benefits, all patients as well as a safety cohort of 9 subsequent cases decided to continue the imatinib therapy. After adjusting the target international normalized ratio (INR) to around 2.0, no further cases of SDH occurred during 50 patient-years. CONCLUSIONS: Long-term treatment with imatinib may improve the functional class and quality of life. Single cases might even attain hemodynamic remission. The occurrence of 5% SDH per patient-years is concerning. However, adjusting the INR to around 2.0 might obviate this complication.

Coronary artery disease in lung transplant candidates: role of routine invasive assessment.

BACKGROUND: An atherosclerotic disease burden sufficient to put lung transplant candidates at risk for end-organ disease after transplantation is considered to be a relative contraindication for lung transplantation. OBJECTIVES: The aim of this study was to assess our current practice of cardiac workup by coronary angiography in lung transplant candidates ≥50 years of age. METHODS: We retrospectively analyzed 50 consecutive lung transplant candidates ≥50 years of age in which coronary angiography was performed at the University Hospital Zurich (2009-2013). For every patient, the risk of developing an acute coronary event was estimated by using a recalibrated version of the PROCAM study calculator for the Swiss population. RESULTS: The median estimated risk of developing an acute coronary event within 10 years in the study cohort (n = 50) was 4.2% (interquartile range 1.9-7.6), which is considered to be a low risk. Sixteen percent of patients were considered to be at intermediate risk. In 66% of patients, coronary angiography showed no coronary artery disease (CAD). In 28% of patients, CAD without significant stenosis was diagnosed. In 6% of patients, significant coronary stenosis was detected requiring percutaneous coronary intervention. No correlation between the coronary status and the risk score or cardiovascular risk profile was found. CONCLUSIONS: The high prevalence of asymptomatic CAD in lung transplant candidates without correlation to a common clinical risk score supports the important role of coronary angiography for the assessment of coronary artery status. This approach might prevent cardiovascular events and improve long-term survival after transplantation.

Long-term data from the Swiss pulmonary hypertension registry.

BACKGROUND: Registries are important for real-life epidemiology on different pulmonary hypertension (PH) groups. OBJECTIVE: To provide long-term data of the Swiss PH registry of 1998-2012. METHODS: PH patients have been classified into 5 groups and registered upon written informed consent at 5 university and 8 associated hospitals since 1998. New York Heart Association (NYHA) class, 6-min walk distance, hemodynamics and therapy were registered at baseline. Patients were regularly followed, and therapy and events (death, transplantation, endarterectomy or loss to follow-up) registered. The data were stratified according to the time of diagnosis into prevalent before 2000 and incident during 2000-2004, 2005-2008 and 2009-2012. RESULTS: From 996 (53% female) PH patients, 549 had pulmonary arterial hypertension (PAH), 36 PH due to left heart disease, 127 due to lung disease, 249 to chronic thromboembolic PH (CTEPH) and 35 to miscellaneous PH. Age and BMI significantly increased over time, whereas hemodynamic severity decreased. Overall, event-free survival was 84, 72, 64 and 58% for the years 1-4 and similar for time periods since 2000, but better during the more recent periods for PAH and CTEPH. Of all PAH cases, 89% had target medical therapy and 43% combination therapy. Of CTEPH patients, 14 and 2% underwent pulmonary endarterectomy or transplantation, respectively; 87% were treated with PAH target therapy. CONCLUSION: Since 2000, the incident Swiss PH patients registered were older, hemodynamically better and mostly treated with PAH target therapies. Survival has been better for PAH and CTEPH diagnosed since 2008 compared with earlier diagnosis or other classifications.

Kinetics of microRNA Expression in Bronchoalveolar Lavage Fluid Samples.

Levels of microRNAs (miRNAs) are increasingly assessed in biological fluids, for example, in samples obtained by bronchoalveolar lavage (BAL). "Post-collection kinetics" of miRNA expression levels, however, have not been investigated to date. In these experiments, we analyzed the dynamic expression profile of 5 different miRNAs (miR-17, miR-19b, miR-20b, miR-125a, and miR-223-3p) in BAL within the first 24 h following collection by routine bronchoscopy. miRNAs were quantified 0, 1, 4, 8, and 24 h after collection in samples that were kept at 4 °C or at room temperature. The expression of all five miRNAs was found to remain stable between the first 8 h after collection. 24 h after collection miRNAs faced substantial alterations in their expression profile. These data emphasize that BAL samples intended for further miRNA analysis can be handled at room temperature within the first 8 h after bronchoscopy.