Haematological features of telomere biology disorders diagnosed in adulthood: A French nationwide study of 127 patients.

Data on haematological features of telomere biology disorders (TBD) remain scarce. We describe haematological, extra-haematological characteristics and prognosis of 127 genetically confirmed TBD patients diagnosed after the age of 15. Ninety-three index cases and 34 affected relatives were included. At diagnosis of TBD, 76.3% of index cases had haematological features, half pulmonary features and a third liver features. At diagnosis, bone marrow failure (BMF) was present in 59 (46.5%), myelodysplastic syndrome (MDS) in 22 (17.3%) and acute myeloid leukaemia (AML) in 2 (1.6%) while 13 (10.2%) developed or worsened bone marrow involvement during follow-up. At diagnosis, compared to MDS/AML patients, BMF patients were younger (median 23.1 years vs. 43.8, p = 0.007), and had a better outcome (4-year overall survival 76.3% vs. 31.8%, p < 0.001). While frequencies and burden of cytogenetical and somatic mutations increased significantly in myeloid malignancies, some abnormalities were also observed in patients with normal blood counts and BMF, notably somatic spliceosome variants. Solid cancers developed in 8.7% patients, mainly human papillomavirus-related cancers and hepatocellular carcinomas. TBD is a multiorgan progressive disease. While BMF is the main haematological disorder, high-risk myeloid malignancies are common, and are, together with age, the only factors associated with a worse outcome.

European Respiratory Society guidelines for the Diagnosis and Management of Pulmonary Alveolar Proteinosis.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a rare syndrome caused by several distinct diseases leading to progressive dyspnoea, hypoxemia, risk of respiratory failure and early death due to accumulation of proteinaceous material in the lungs. Diagnostic strategies may include computed tomography (CT) of the lungs, bronchoalveolar lavage, evaluation of antibodies against granulocyte macrophage colony stimulating factor (GM-CSF), genetic testing, and, eventually, lung biopsy. The management options are focused at removing the proteinaceous material by whole lung lavage (WLL), augmentation therapy with GM-CSF, rituximab, plasmapheresis, and lung transplantation. The presented diagnostic and management guideline aim to provide guidance to physicians managing patients with PAP. METHODS: A European Respiratory Society Task Force committee composed of clinicians, methodologists, and patients with experience in PAP developed recommendations in accordance with the ERS Handbook for Clinical Practice Guidelines and the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) approach. This included a systematic review of the literature and application of the GRADE approach to assess the certainty of the evidence and strength of recommendations. The committee formulated five PICO (Patients, Intervention, Comparison, Outcomes) questions, and two narrative questions to develop specific evidence-based recommendations. RESULTS: The Task Force committee developed recommendations for five PICOs. These included management of PAP with WLL, GM-CSF augmentation therapy, rituximab, plasmapheresis, and lung transplantation. Also, the committee made recommendations regarding the use of GM-CSF antibody testing, diagnostic bronchoalveolar lavage (BAL) and biopsy based on narrative questions.In addition to the recommendations, the committee provided information on the hierarchy of diagnostic interventions and therapy. CONCLUSIONS: The diagnosis of PAP is based on CT and BAL cytology or lung histology, whereas diagnosis of specific PAP-causing diseases requires GM-CSF antibody testing or genetic analysis. There are several therapies including WLL and augmentation therapy with GM-CSF available to treat PAP, but supporting evidence is still limited.

Cystic lung in sarcoidosis: Clinico-radiologic characteristic and evolution.

BACKGROUND AND OBJECTIVE: Sarcoidosis can manifest with atypical findings on chest computed tomography (CT). Cysts are a rare manifestation of lung sarcoidosis. The aim of the study was to describe a series of patients with cystic sarcoidosis and their clinical-radiological characteristics and progression. METHODS: In this retrospective, bicentric study we recruited all patients affected by sarcoidosis with lung cystic lesions at chest CT. We collected clinical characteristics, pulmonary tests and tracked number, distribution and size of the cysts at diagnosis and at the last evaluation. RESULTS: Twelve patients (6 males, median age 53 years) were identified (prevalence: 1.9%; 95% Confidence Interval: 0.8%-2.9%). All patients presented multiple cystic lesions (median number: 14 [range: 2-216]) with a bilateral distribution in 10/12, micronodules and nodules in 11/12 and fibrotic lesions in 4/12. Seven patients had normal lung function test, three had an obstructive syndrome, one had a restrictive syndrome and one had coexistence of both. During follow-up (median: 10 years [range 1-16 years]), an increase of the number of cysts was observed in four patients. At last evaluation, 3/12 patients experienced a decline of forced vital capacity >10% and 3/12 patients a decline of diffusing capacity for carbon monoxide (DLCO) >10%. A lower DLCO at diagnosis, and the presence of nodules or fibrotic lesions on CT were associated with an increase in the number of cysts. CONCLUSION: Cystic lung lesions are rare in patients with sarcoidosis and do not influence long term prognosis.

Alemtuzumab-based conditioning regimen before hematopoietic stem cell transplantation in patients with short telomere syndromes: a retrospective study of the SFGM-TC.

While HSCT is the only curative option for patients with short telomere syndromes (STSs) and severe bone marrow failure (BMF) or myeloid malignancies (MM), their increase sensitivity to conditioning regimen strongly affect outcomes. To minimize HSCT related mortality, alemtuzumab-based conditioning regimens have been proposed, but the number of patients transplanted with those regimens reported in the literature remains very low. We retrospectively analyzed outcome of adults and adolescents with STSs transplanted after an alemtuzumab, fludarabine and cyclophosphamide based regimen registered by the SFGM-TC. Seven patients were transplanted for a BMF and 5 for a MM (median age 34 years, (IQR [22-45])). The 2-year GRFS for patients with MM was 20% (95% CI [3;100]), and 57% (95% CI [30;100]) in others. In univariate (hazard ratio, HR = 6, 95% CI [1;31]) and multivariate analysis (HR = 26, 95% CI [2;414]) stem cell source was a predictive factor for GRFS. Three of the 5 patients with pre-transplant MM relapsed and 2 of them died at last follow up. The 2-year OS was 66% (95% CI [43;99]) in the whole cohort with a median follow up of 32 months (IQR [13-56]). In conclusion, Alemtuzumab-based conditioning regimen with bone marrow is an option for patients with STSs and BMF, but others modalities have to be explored for patients with MM.

Epidemiology of childhood interstitial lung disease in France: the RespiRare cohort.

INTRODUCTION: Interstitial lung disease in children (chILD) are rare and mostly severe lung diseases. Very few epidemiological data are available in limited series of patients. The aim of this study was to assess the prevalence and incidence of chILD in France. METHODS: We performed within the RespiRare network a multicentre retrospective observational study in patients with chILD from 2000 to 2022 and a prospective evaluation of chILD's incidence between February 2022 and 2023. RESULTS: chILD was reported in 790 patients in 42 centres. The estimated 2022 prevalence in France was 44 /million children (95% CI 40.76 to 47.46) and the computed incidence was 4.4 /million children (95% CI 3.44 to 5.56). The median age at diagnosis was 3 months with 16.9% of familial forms. Lung biopsy and genetic analyses were performed in 23.4% and 76.9%, respectively. The most frequent chILD aetiologies in the <2 years group were surfactant metabolism disorders (16.3%) and neuroendocrine cell hyperplasia of infancy (11.8%), and in the 2-18 years group diffuse alveolar haemorrhage (12.2%), connective tissue diseases (11.4%), hypersensitivity pneumonitis (8.8%) and sarcoidosis (8.8%). The management included mainly oxygen therapy (52%), corticosteroid pulses (56%), oral corticosteroids (44%), azithromycin (27.2%), enteral nutrition (26.9%), immunosuppressants (20.3%) and hydroxychloroquine (15.9%). The 5-year survival rate was 57.3% for the patients diagnosed before 2 years and 86% between 2 and 18 years. CONCLUSION: This large and systematic epidemiological study confirms a higher incidence and prevalence of chILD than previously described. In order to develop international studies, efforts are still needed to optimise the case collection and to harmonise diagnostic and management practices.

Size-matching in lung transplantation by computed tomography for end-stage interstitial disease: a retrospective analysis.

Background: Size matching between donors and recipients is a major issue in lung transplantation (LTx), especially in patients with restrictive lung disease (RLD). This study aims to evaluate computed tomography (CT) as an additional method for defining the total lung capacity (TLC) in patients with end-stage interstitial disease awaiting LTx. Methods: Clinical data and CT scans from patients who underwent a first LTx from January 2014 to July 2018 in Bichat Hospital, Paris, were prospectively included in a database. CT TLC (ctTLC) was retrospectively calculated after semi-automatic contouring of the parenchyma and compared with measured TLC (mTLC) and predicted TLC (pTLC) values. Results: The study group included 89 patients (male:female =68:21; mean age, 59.5±10.0 years). The time between pulmonary function tests (PFTs) and CT scan was 162±270 days [median, 67 days; interquartile range (IQR), 0-233 days]. ctTLC was inferior to mTLC and pTLC (respectively 2,979±1,001 mL, 3,530±1,077 and 6,381±955 mL, P<0.001). The relative difference between CT lung volume (ctLV) and measured lung volume (mLV) was higher on the left than on the right side (25.4% vs. 16.3%, respectively, P=0.11). After exclusion of two outliers, we found a significant correlation between ctTLC and mTLC (r=0.762, P<0.001). Conclusions: CT volume is a feasible method to assess TLC in patients with end-stage interstitial disease awaiting LTx. This study highlights potential size-mismatch for graft selection before LTx and opens the perspective of a prospective trial evaluating impact of size-matching by donor-recipient (D-R) ctTLC ratio on postoperative outcomes.

An underrecognized phenotype of pulmonary emphysema with marked pulmonary gas exchange but with mild or moderate airway obstruction.

In patients with pulmonary emphysema and mild to moderate airflow limitation, one does not expect the features marked exertional dyspnea and hypoxemia as well as a profound decrease in diffusing capacity of the lung for carbon monoxide (DLCO). Here we describe this phenotype and its prognosis. From our database, we retrospectively selected cases associating emphysema, exertional breathlessness, O2 requirement at least upon exercise, forced expiratory volume in 1 sec (FEV1) ≥ 50% predicted, and DLCO ≤ 50% predicted, without associated combined pulmonary fibrosis and emphysema, right-to-left shunt, or severe pulmonary hypertension. Over a 12-year period, we identified 16 patients with emphysema and the above presentation. At the initial evaluation, the median age was 62 years (interquartile range 53.8-68.9). The median FEV1 and DLCO% predicted and mean pulmonary artery pressure were 86 (65-95)%, 38 (31-41)%, and 20 (17-25) mm Hg, respectively. On room air, the median arterial partial pressure of oxygen and partial pressure of carbon dioxide in arterial blood were 63.5 (55.8-69) mm Hg and 34.5 (31-36) mm Hg with increased median alveolar-arterial oxygen difference (46 [39-51] mm Hg). After the initial evaluation, the respiratory condition worsened in 13 of 14 (92.8%) patients with one or more re-evaluations (median follow-up 2.6 [0.9-5.8] years). In 12, lung transplantation was considered. Four patients died after 5.8, 5.7, 7.1, and 0.8 years of follow-up, respectively. We describe an underrecognized phenotype of pulmonary emphysema featuring a particular profile characterized by marked exertional dyspnea, impaired pulmonary gas exchange with low DLCO and marked oxygen desaturation at least on exercise but with mild or moderate airway obstruction.

RPA3-UMAD1 rs12702634 and rheumatoid arthritis-associated interstitial lung disease in European ancestry.

Objective: Recently, a genome-wide association study identified an association between RA-associated interstitial lung disease (ILD) and RPA3-UMAD1 rs12702634 in the Japanese population, especially for patients with a usual interstitial pneumonia (UIP) pattern. We aimed to replicate this association in a European population and test for interaction with MUC5B rs35705950. Methods: In this genetic case-control association study, patients with RA and ILD and controls with RA and no ILD were included from France, the USA and the Netherlands. Only cases and controls from European genetic ancestries determined by principal components analysis were included in the analyses. RA was defined by the 1987 ACR or 2010 ACR/EULAR criteria and ILD by chest high-resolution CT scan, except in the control dataset from the Netherlands, where the absence of ILD was determined by chart review. Patients were genotyped for RPA3-UMAD1 rs12702634 and MUC5B rs35705950. Associations were tested using logistic regression adjusted for sex, age at RA onset, age at ILD onset or at certified absence of ILD, tobacco smoking status and country of origin. Results: Among the 883 patients included, 322 were RA-ILD cases (36.5%). MUC5B rs35705950 was strongly associated with RA-ILD in all datasets {combined adjusted odds ratio [OR] 2.9 [95% CI 2.1, 3.9], P = 1.1 × 10-11. No association between RPA3-UMAD1 rs12702634 and RA-ILD was observed [combined OR 1.2 (95% CI 0.8, 1.6), P = 0.31. No interaction was found between RPA3-UMAD1 rs12702634 and MUC5B rs35705950 (P = 0.70). Conclusion: Our findings did not support a contribution of RPA3-UMAD1 rs12702634 to the overall RA-ILD susceptibility in the European population.

Nocardia Infection in Patients With Anti-Granulocyte-Macrophage Colony-Stimulating Factor Autoantibodies: A Prospective Multicenter French Study.

Background: Nocardiosis, a bacterial opportunistic infection caused by Nocardia spp, has recently been reported in patients with anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies, but insufficient data are available about disease presentation, outcomes, and occurrence of autoimmune pulmonary alveolar proteinosis (aPAP) in this population. Methods: We performed a prospective, multicenter, nationwide study in France and included patients with a Nocardia infection who had anti-GM-CSF autoantibodies. We describe their clinical, microbiological, and radiological characteristics, and their outcome at 1 year of follow-up. Results: Twenty patients (18 [90%] male) were included, with a median age of 69 (interquartile range, 44-75) years. The organs most frequently involved were the brain (14/20 [70%]) and the lung (12/20 [60%]). Half of the infections were disseminated (10/20 [50%]). Nocardia identification was predominantly made in abscess fluid (17/20 [85%]), among which 10 (59%) were brain abscesses. The 1-year all-cause mortality was 5% (1/20), and only 1 case of aPAP (1/20 [5%]) occurred during the follow-up period. Conclusions: Nocardiosis with anti-GM-CSF autoantibodies is associated with a low mortality rate despite a high incidence of brain involvement. Although the occurrence of aPAP was infrequent during the 1-year follow-up period, long-term clinical data are needed to fully understand the potential relationship between nocardiosis, anti-GM-CSF autoantibodies, and aPAP.

Syndromic genetic causes of pulmonary fibrosis.

PURPOSE OF REVIEW: The identification of extra-pulmonary symptoms plays a crucial role in diagnosing interstitial lung disease (ILD). These symptoms not only indicate autoimmune diseases but also hint at potential genetic disorders, suggesting a potential overlap between genetic and autoimmune origins. RECENT FINDINGS: Genetic factors contributing to ILD are predominantly associated with telomere (TRG) and surfactant-related genes. While surfactant-related gene mutations typically manifest with pulmonary involvement alone, TRG mutations were initially linked to syndromic forms of pulmonary fibrosis, known as telomeropathies, which may involve hematological and hepatic manifestations with variable penetrance. Recognizing extra-pulmonary signs indicative of telomeropathy should prompt the analysis of TRG mutations, the most common genetic cause of familial pulmonary fibrosis. Additionally, various genetic diseases causing ILD, such as alveolar proteinosis, alveolar hemorrhage, or unclassifiable pulmonary fibrosis, often present as part of syndromes that include hepatic, hematological, or skin disorders. SUMMARY: This review explores the main genetic conditions identified over the past two decades.

A roadmap to precision treatments for familial pulmonary fibrosis.

Interstitial lung diseases (ILDs) in adults and children (chILD) are a heterogeneous group of lung disorders leading to inflammation, abnormal tissue repair and scarring of the lung parenchyma often resulting in respiratory failure and death. Inherited factors directly cause, or contribute significantly to the risk of developing ILD, so called familial pulmonary fibrosis (FPF), and monogenic forms may have a poor prognosis and respond poorly to current treatments. Specific, variant-targeted or precision treatments are lacking. Clinical trials of repurposed drugs, anti-fibrotic medications and specific treatments are emerging but for many patients no interventions exist. We convened an expert working group to develop an overarching framework to address the existing research gaps in basic, translational, and clinical research and identified areas for future development of preclinical models, candidate medications and innovative clinical trials. In this Position Paper, we summarise working group discussions, recommendations, and unresolved questions concerning precision treatments for FPF.

High risk of lung cancer in surfactant-related gene variant carriers.

BACKGROUND: Several rare surfactant-related gene (SRG) variants associated with interstitial lung disease are suspected to be associated with lung cancer, but data are missing. We aimed to study the epidemiology and phenotype of lung cancer in an international cohort of SRG variant carriers. METHODS: We conducted a cross-sectional study of all adults with SRG variants in the OrphaLung network and compared lung cancer risk with telomere-related gene (TRG) variant carriers. RESULTS: We identified 99 SRG adult variant carriers (SFTPA1 (n=18), SFTPA2 (n=31), SFTPC (n=24), ABCA3 (n=14) and NKX2-1 (n=12)), including 20 (20.2%) with lung cancer (SFTPA1 (n=7), SFTPA2 (n=8), SFTPC (n=3), NKX2-1 (n=2) and ABCA3 (n=0)). Among SRG variant carriers, the odds of lung cancer was associated with age (OR 1.04, 95% CI 1.01-1.08), smoking (OR 20.7, 95% CI 6.60-76.2) and SFTPA1/SFTPA2 variants (OR 3.97, 95% CI 1.39-13.2). Adenocarcinoma was the only histological type reported, with programmed death ligand-1 expression ≥1% in tumour cells in three samples. Cancer staging was localised (I/II) in eight (40%) individuals, locally advanced (III) in two (10%) and metastatic (IV) in 10 (50%). We found no somatic variant eligible for targeted therapy. Seven cancers were surgically removed, 10 received systemic therapy, and three received the best supportive care according to their stage and performance status. The median overall survival was 24 months, with stage I/II cancers showing better survival. We identified 233 TRG variant carriers. The comparative risk (subdistribution hazard ratio) for lung cancer in SRG patients versus TRG patients was 18.1 (95% CI 7.1-44.7). CONCLUSIONS: The high risk of lung cancer among SRG variant carriers suggests specific screening and diagnostic and therapeutic challenges. The benefit of regular computed tomography scan follow-up should be evaluated.

Rheumatoid arthritis and idiopathic pulmonary fibrosis: a bidirectional Mendelian randomisation study.

BACKGROUND: A usual interstitial pneumonia (UIP) pattern of lung injury is a key feature of idiopathic pulmonary fibrosis (IPF) and is also observed in up to 40% of individuals with rheumatoid arthritis (RA)-associated interstitial lung disease (RA-ILD). The RA-UIP phenotype could result from either a causal relationship of RA on UIP or vice versa, or from a simple co-occurrence of RA and IPF due to shared demographic, genetic or environmental risk factors. METHODS: We used two-sample bidirectional Mendelian randomisation (MR) to test the hypothesis of a causal effect of RA on UIP and of UIP on RA, using variants from genome-wide association studies (GWAS) of RA (separately for seropositive (18 019 cases and 991 604 controls) and seronegative (8515 cases and 1 015 471 controls) RA) and of IPF (4125 cases and 20 464 controls) as genetic instruments. Sensitivity analyses were conducted to assess the robustness of the results to violations of the MR assumptions. FINDINGS: IPF showed a significant causal effect on seropositive RA, with developing IPF increasing the risk of seropositive RA (OR=1.06, 95% CI: 1.04 to 1.08, p<0.001) which was robust under all models. For the MR in the other direction, seropositive RA showed a significant protective effect on IPF (OR=0.93; 95% CI: 0.87 to 0.99; p=0.032), but the effect was not significant when sensitivity analyses were applied. This was likely because of bias due to exclusion of patients with RA from among the cases in the IPF GWAS, or possibly because our genetic instruments did not fully capture the effect of the complex human leucocyte antigen region, the strongest RA genetic risk factor. INTERPRETATION: Our findings support the hypothesis that RA-UIP may be due to a cause-effect relationship between UIP and RA, rather than due to a coincidental occurrence of IPF in patients with RA. The significant causal effect of IPF on seropositive RA suggests that pathomechanisms involved in the development of UIP may promote RA, and this may help inform future guidelines on screening for ILD in patients with RA.

Successful lung transplantation in genetic methionyl-tRNA synthetase-related alveolar proteinosis/lung fibrosis without recurrence under methionine supplementation: Medium-term outcome in 4 cases.

Pulmonary alveolar proteinosis (PAP) results from the accumulation of lipoproteinaceous material in the alveoli and alveolar macrophages, and can be associated with pulmonary fibrosis, with a need for lung transplantation (LTx). Causes of PAP are autoimmune (90%-95%), secondary (5%), or hereditary (<1%). Patients with hereditary PAP are generally not considered for isolated LTx, due to the high probability of recurrence after LTx, and only a challenging scenario with sequential LTx followed by hematopoietic stem cell transplantation (HSCT) was reported as successful. Recently, a new genetic cause of PAP linked to mutations in the methionyl-tRNA synthetase (MARS) gene has been reported, with a highly variable clinical presentation. Because clinical correction of the defective MARS activity with methionine supplementation has been reported in nontransplanted children, we reassessed the feasibility of LTx for candidates with MARS-related PAP/fibrosis. We report 3 cases of LTx performed for MARS-related pulmonary alveolar proteinosis-pulmonary fibrosis without recurrence under methionine supplementation, whereas another fourth case transplanted without supplementation had fatal PAP recurrence. These results suggest the effectiveness of methionine in correcting defective MARS activity and also looking for this very rare diagnosis in case of unclassified PAP/fibrosis. It argues for not excluding the feasibility of isolated LTx in patients with MARS mutation.

Chronic interstitial lung disease associated with systemic lupus erythematosus: A multicentric study of 89 cases.

BACKGROUND AND OBJECTIVE: Chronic interstitial lung disease (ILD) occurs rarely with systemic lupus erythematosus (SLE) as compared with other connective tissue diseases. This multicentric retrospective study of patients with SLE-ILD from the OrphaLung and French SLE networks during 2005-2020 aimed to describe the characteristics of patients with SLE-ILD and analyse factors associated with prognosis. METHODS: We analysed data for 89 patients with SLE-ILD (82 women, 92.1%) (median age at SLE diagnosis: 35 years [interquartile range 27-47]). All patients met the 2019 EULAR/ACR criteria for the diagnosis of SLE. RESULTS: Forty two (47.2%) patients were positive for anti-ribonuclear protein antibodies and 45 (50.6%) for anti SSA/Ro antibodies. A total of 58 (65.2%) patients had another connective tissue disease: Sjögren's syndrome (n = 33, 37.1%), systemic sclerosis (n = 14, 15.7%), inflammatory myopathy (n = 6, 6.7%), or rheumatoid arthritis (n = 6, 6.7%). ILD was diagnosed along with SLE in 25 (28.1%) patients and at a median of 6 (0-14) years after the SLE diagnosis. The most frequent CT pattern was suggestive of non-specific interstitial pneumonia (n = 41, 46.0%) with or without superimposed organizing pneumonia. After a median follow-up of 86.5 [39.5-161.2] months, 18 (20.2%) patients had died and 6 (6.7%) underwent lung transplantation. The median 5-year and 10-year transplantation-free survival were 96% (92-100) and 87% (78-97). In total, 44 (49.4%) patients showed ILD progression. Cutaneous manifestations and Raynaud's phenomenon were associated with better survival. Only forced vital capacity was significantly associated with survival and ILD progression. CONCLUSION: ILD is a rare manifestation of SLE with good overall prognosis but with possible risk of ILD progression. Patients with SLE-ILD frequently have another connective tissue disease.

Similarities and differences of interstitial lung disease associated with pathogenic variants in SFTPC and ABCA3 in adults.

BACKGROUND AND OBJECTIVE: Variants in surfactant genes SFTPC or ABCA3 are responsible for interstitial lung disease (ILD) in children and adults, with few studies in adults. METHODS: We conducted a multicentre retrospective study of all consecutive adult patients diagnosed with ILD associated with variants in SFTPC or ABCA3 in the French rare pulmonary diseases network, OrphaLung. Variants and chest computed tomography (CT) features were centrally reviewed. RESULTS: We included 36 patients (median age: 34 years, 20 males), 22 in the SFTPC group and 14 in the ABCA3 group. Clinical characteristics were similar between groups. Baseline median FVC was 59% ([52-72]) and DLco was 44% ([35-50]). An unclassifiable pattern of fibrosing ILD was the most frequent on chest CT, found in 85% of patients, however with a distinct phenotype with ground-glass opacities and/or cysts. Nonspecific interstitial pneumonia and usual interstitial pneumonia were the most common histological patterns in the ABCA3 group and in the SFTPC group, respectively. Annually, FVC and DLCO declined by 1.87% and 2.43% in the SFTPC group, respectively, and by 0.72% and 0.95% in the ABCA3 group, respectively (FVC, p = 0.014 and DLCO , p = 0.004 for comparison between groups). Median time to death or lung transplantation was 10 years in the SFTPC group and was not reached at the end of follow-up in the ABCA3 group. CONCLUSION: SFTPC and ABCA3-associated ILD present with a distinct phenotype and prognosis. A radiologic pattern of fibrosing ILD with ground-glass opacities and/or cysts is frequently found in these rare conditions.

Anti-mutated citrullinated vimentin antibodies are increased in IPF patients.

INTRO: An increased prevalence of serum anti-MCV antibody is observed in the serum of patients with idiopathic pulmonary fibrosis (IPF) but the clinical relevance of these antibodies is unknown. METHODS: Patients from our center with a diagnosis of IPF according to the 2018 ATS/ERS/JRS/ALAT guidelines and at least one anti-MCV assay available were selected. All patients were part of the prospective cohort European IPF registry and selected between 03/2010 and 03/2018. We constituted two groups of patients according to the anti-MCV status at baseline to compare their characteristics at baseline and the evolution of lung function, survival and/or transplantation status. RESULTS: Anti-MCV data were available for 101 patients, of whom 86 had complete clinical data available. Twenty-nine (34 %) patients had a positive anti-MCV assay (MCV+), at a low level in most patients (29 UI/mL [IQR 25-40]), and 57 (66 %) patients a negative assay (MCV-). MCV+ patients were 20 men and 9 women, with a median age of 73 years [IQR 67-78]. MCV- patients were 49 men and 8 women with a median age of 72 years [IQR 64-77]. Sixty-two (75 %) patients were ex-smokers and 5 (6 %) were active smokers. Median cumulative tobacco smoke exposure was 22.5 (15.0-38.6) and was similar in both groups. Lung function test results and HRCT pattern distribution was similar in both groups at baseline. The median duration of follow-up was 3.5 years [IQR 2.1-5.0]. Lung function decline was similar in both groups. During the study period, 31 (36 %) patients died or have been transplanted with no difference in transplant-free survival status between the two groups. CONCLUSION: Low level anti-MCV autoimmunity was prevalent in IPF patients.