Pulmonary alveolar proteinosis (PAP) is a rare pulmonary disease characterised by alveolar accumulation of surfactant. It may result from mutations in surfactant proteins or granulocyte macrophage-colony stimulating factor (GM-CSF) receptor genes, it may be secondary to toxic inhalation or haematological disorders, or it may be auto-immune, with anti-GM-CSF antibodies blocking activation of alveolar macrophages. Auto-immune alveolar proteinosis is the most frequent form of PAP, representing 90% of cases. Although not specific, high-resolution computed tomography shows a characteristic “crazy paving” pattern. In most cases, bronchoalveolar lavage findings establish the diagnosis. Whole lung lavage is the most effective therapy, especially for auto-immune disease. Novel therapies targeting alveolar macrophages (recombinant GM-CSF therapy) or anti-GM-CSF antibodies (rituximab and plasmapheresis) are being investigated. Our knowledge of the pathophysiology of PAP has improved in the past 20 yrs, but therapy for PAP still needs improvement.

Question addressed by the study: Methotrexate (MTX) is a key anchor drug for rheumatoid arthritis (RA) management. Fibrotic interstitial lung disease (ILD) is a common complication of RA. Whether MTX exposure increases the risk of ILD in patients with RA is disputed. We aimed to evaluate the association of prior MTX use with development of RA-ILD.Methods: Through a case–control study design with discovery and international replication samples, we examined the association of MTX exposure with ILD in 410 patients with chronic fibrotic ILD associated with RA (RA-ILD) and 673 patients with RA without ILD. Estimates were pooled over the different samples using meta-analysis techniques.Results: Analysis of the discovery sample revealed an inverse relationship between MTX exposure and RA-ILD (adjusted OR 0.46, 95% CI 0.24–0.90; p=0.022), which was confirmed in the replication samples (pooled adjusted OR 0.39, 95% CI 0.19–0.79; p=0.009). The combined estimate using both the derivation and validation samples revealed an adjusted OR of 0.43 (95% CI 0.26–0.69; p=0.0006). MTX ever-users were less frequent among patients with RA-ILD compared to those without ILD, irrespective of chest high-resolution computed tomography pattern. In patients with RA-ILD, ILD detection was significantly delayed in MTX ever-users compared to never-users (11.4±10.4 years and 4.0±7.4 years, respectively; p<0.001).Answer to the question: Our results suggest that MTX use is not associated with an increased risk of RA-ILD in patients with RA, and that ILD was detected later in MTX-treated patients.

Mucosa-associated lymphoid tissue-derived (MALT) lymphoma, a low grade B-cell extranodal lymphoma, is the most frequent subset of primary pulmonary lymphoma. Our objective was to evaluate the initial extent of disease and to analyse the characteristics and long-term outcome of these patients.All chest and pathological departments of teaching hospitals in Paris were contacted in order to identify patients with a histological diagnosis of primary pulmonary lymphoma of the MALT subtype.63 cases were identified. The median age was 60 yrs. 36% of cases had no symptoms at diagnosis. 46% of patients had at least one extrapulmonary location of lymphoma. The estimated 5- and 10-yr overall survival rates were 90% and 72%, respectively. Only two of the nine observed deaths were related to lymphoma. Age and performance status were the only two adverse prognostic factors for survival. Extrapulmonary location of lymphoma was not a prognostic factor for overall survival or for progression-free survival. Treatment with cyclophosphamide or anthracyclin was associated with shorter progression-free survival, when compared with chlorambucil.The survival data confirm the indolent nature of pulmonary MALT lymphoma. Better progression-free survival was observed with chlorambucil when compared with cyclophosphamide or anthracyclin.

Telomerase reverse transcriptase (TERT) or telomerase RNA (TERC) gene mutation is a major monogenic cause of pulmonary fibrosis. Sequencing ofTERT/TERCgenes is proposed to patients with familial pulmonary fibrosis. Little is known about the possible predictors of this mutation and its impact on prognosis.We retrospectively analysed all the genetic diagnoses made between 2007–2014 in patients with pulmonary fibrosis. We evaluated the prevalence ofTERT/TERCdisease-associated variant (DAV), factors associated with a DAV, and the impact of the DAV on survival.237 patients with pulmonary fibrosis (153 with familial pulmonary fibrosis, 84 with telomere syndrome features without familial pulmonary fibrosis) were tested forTERT/TERCDAV. DAV was diagnosed in 40 patients (16.8%), including five with non-idiopathic interstitial pneumonia. Prevalence ofTERT/TERCDAV did not significantly differ between patients with familial pulmonary fibrosis or with only telomere syndrome features (18.2%versus16.4%). Young age, red blood cell macrocytosis, and low platelet count were associated with the presence of DAV; the probability of DAV was increased for patients 40–60 years. Transplant-free survival was lower with than withoutTERT/TERCDAV (4.2versus7.2 years; p=0.046).TERT/TERCDAV were associated with specific clinical and biological features and reduced transplant-free survival.

More than half of patients with Covid-19 pneumonia exhibit abnormal lung function 30 days after symptoms onset, without clear relationship with pneumonia extent on chest-CT. This pleads for systematic and long-term follow-up of patients with Covid.

A polymorphism on the MUC5B promoter (rs35705950) has been associated with idiopathic pulmonary fibrosis (IPF) but not with systemic sclerosis (SSc) with interstitial lung disease (ILD). We genotyped the MUC5B promoter in the first 142 patients of the French national prospective cohort of IPF, in 981 French patients with SSc (346 ILD), 598 Italian patients with SSc (207 ILD), 1383 French controls and 494 Italian controls. A meta-analysis was performed including all American data available. The T risk allele was present in 41.9% of the IPF patients, 10.8% of the controls (P = 2×10^–44), OR 6.3 [4.6–8.7] for heterozygous patients and OR 21.7 [10.4–45.3] for homozygous patients. Prevalence of the T allele was not modified according to age, gender, smoking in IPF patients. However, none of the black patients with IPF presented the T allele. The prevalence of the T risk allele was similar between French (10%) and Italian (12%) cohorts of SSc whatever the presence of an ILD (11.1% and 13.5%, respectively). Meta-analysis confirmed the similarity between French, Italian and American cohorts of IPF or SSc-ILD. This study confirms 1) an association between the T allele risk and IPF, 2) an absence of association with SSc-ILD, suggesting different pathophysiology.