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BACKGROUND: Tinzaparin could be easier to manage than unfractionated heparin in patients with severe renal impairment. However, clinical and pharmacologic data regarding its use in such patients are lacking. OBJECTIVES: The aims of this study were to determine, in patients with estimated glomerular filtration rate (eGFR) of <30 mL.minâ»1, tinzaparin pharmacokinetics (PK) parameters using a population PK approach and bleeding and thrombotic complications. METHODS: We performed a retrospective observational single-center study, including in-patients with eGFR of <30 mL.minâ»1 receiving prophylactic (4500 IU.dâ»1) or therapeutic (175 IU.kgâ»1.dâ»1) tinzaparin. Measured anti-Xa levels were analyzed using a nonlinear mixed-effects modeling approach. Individual predicted tinzaparin exposure markers at steady state were calculated for each patient and dosing regimen. The PK was also evaluated through Monte Carlo simulations based on the final covariate model parameter estimates. RESULTS: Over a 22-month period, 802 tinzaparin treatment periods in 623 patients were analyzed: two-thirds received a prophylactic dose, 66% had an eGFR of <20 mL.minâ»1, and 25% were on renal replacement therapy. In patients for whom anti-Xa measurements were performed (n = 199; 746 values), PK parameters, profiles, and maximum plasma concentrations were comparable with those in patients without renal impairment or in healthy volunteers. In the whole population, major bleeding occurred in 2.4% and 3.5% of patients receiving prophylactic and therapeutic doses over a median 9- and 7-day treatment period, respectively. No patients had thrombotic complications. CONCLUSION: Tinzaparin PK parameters and profiles were not affected by renal impairment. This suggests that tinzaparin, at therapeutic or prophylactic dose, could be an alternative to unfractionated heparin in hospitalized patients with severe renal impairment.
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Apixaban and rivaroxaban have first-line use for many patients needing anticoagulation for venous thromboembolism (VTE). The pharmacokinetics of these drugs in non-obese subjects have been extensively studied, and, while changes in pharmacokinetics have been documented in obese patients, data remain scarce for these anticoagulants. The aim of this study was to perform an external validation of published population pharmacokinetic (PPK) models of apixaban and rivaroxaban in a cohort of obese patients with VTE. A literature search was conducted in the PubMed/MEDLINE, Scopus, and Embase databases following the PRISMA statement. External validation was performed using MonolixSuite software, using prediction-based and simulation-based diagnostics. An external validation dataset from the university hospitals of Brest and Rennes, France, included 116 apixaban pharmacokinetic samples from 69 patients and 121 rivaroxaban samples from 81 patients. Five PPK models of apixaban and 16 models of rivaroxaban were included, according to the inclusion criteria of the study. Two of the apixaban PPK models presented acceptable performances, whereas no rivaroxaban PPK model did. This study identified two published models of apixaban applicable to apixaban in obese patients with VTE. However, none of the rivaroxaban models evaluated were applicable. Dedicated studies appear necessary to elucidate rivaroxaban pharmacokinetics in this population.
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OBJECTIVES: Develop and validate a thorough exposure questionnaire to comprehensively explore crystalline silica (SiO2) exposure in the general population (gender-specific, occupational and non-occupational) and in patients with autoimmune diseases (rheumatoid arthritis (RA), systemic sclerosis (SSc)). METHODS: Lifetime exposures to SiO2 in occupational and non-occupational settings were assessed using a thorough exposure questionnaire. The questionnaire was applied to a general population panel (n = 2911) sampled from the French rolling census, and to unselected patients with SSc (n = 100) and RA (n = 97). Global (GES), occupational (OES) and non-occupational (NOES) exposure scores were assessed in SSc and RA patients, and compared with up to four controls from the general population, matched by age group, sex and tobacco consumption. RESULTS: Patients had higher GES than their matched controls (SSc: P = 0.001; RA: P < 0.0001) due to higher OES (P < 0.0001 for SSc and RA). Men had higher GES than women (SSc: P < 0.0001; RA: P = 0.002) due to higher OES (P < 0.0001 for SSc and RA). The NOES did not differ between men and women. In SSc patients: Men had higher GES than controls (P < 0.0001). Men and women with SSc had higher OES than controls (P < 0.0001). In RA patients: GES and OES were higher in both men (P = 0.00521; P < 0.0001) and women (P < 0.0001; P < 0.0001) than in their respective controls. Women had higher NOES than controls (P = 0.045). CONCLUSION: The lifetime SiO2 exposure gap between RA and SSc patients and controls was substantially due to occupational exposure. In both diseases, men had higher exposure scores than women.
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Artritis Reumatoide , Esclerodermia Sistémica , Masculino , Humanos , Femenino , Estudios Transversales , Factores de Riesgo , Dióxido de Silicio/efectos adversos , Artritis Reumatoide/epidemiología , Esclerodermia Sistémica/epidemiología , Esclerodermia Sistémica/inducido químicamenteRESUMEN
OBJECTIVE: To define a semiquantitative classification of finger pulp blood flow (FPBF) and to evaluate whether this classification could be used to assess FPBF in healthy controls and in systemic sclerosis (SSc) patients. METHODS: Thirty controls and 86 SSc patients were consecutively included. A classification of FPBF including 5 grades (from grade 0 [no signal] to 4 [signal detected on the entire finger pulp, including the subepidermal vascular network]) was evaluated. This classification was explored in basal conditions and after hand baths in hot and cold water in controls. Its relevance was also assessed at room temperature in SSc patients. RESULTS: In controls, power Doppler ultrasonography (PDUS) of FPBF was improved after hot challenge (P = 0.024), whereas cold challenge decreased FPBF (P = 0.001). FPBF correlated with the vasodilation status assessed by the resistivity index of radial arteries (Spearman's correlation coefficient = -0.50, P = 0.0049). Grade 0 was more frequent in SSc patients than in controls (22.1% versus 3.3%; P < 0.05). In SSc patients, grade 0 was associated with severity markers of the digital vasculopathy such as digital ulcers (DUs) (current or past) (P < 0.05) or ulnar artery occlusion (P < 0.05). On the other hand, DUs were less frequent in patients with grade 4 (P < 0.05). A pathologic threshold of <2 (grade 0 or 1) was significantly associated with DUs (odds ratio 6.67 [95% confidence interval 2.31-19.21], P < 0.0001). CONCLUSION: PDUS allowed a semiquantitative evaluation of FBPF in SSc patients and controls. Further studies are warranted to validate these results in independent SSc populations and to compare PDUS to existing tools assessing digital blood flow.
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Arteriopatías Oclusivas , Esclerodermia Sistémica , Úlcera Cutánea , Humanos , Proyectos Piloto , Ultrasonografía , Esclerodermia Sistémica/complicaciones , Dedos/diagnóstico por imagen , Dedos/irrigación sanguíneaRESUMEN
BACKGROUND: Direct oral anticoagulants (DOAC) use remains challenging in obese patients treated for Venous-Thrombo-Embolism (VTE) due to the paucity of prospective and dedicated studies. OBJECTIVE: To assess rivaroxaban and apixaban concentrations at different time-points after intake, in obese patients followed at a thrombosis center and treated for VTE; to define factors associated with DOAC levels outside the on-therapy ranges; and to evaluate bleeding and thrombosis rates during follow-up. METHODS: Observational prospective study in two French University hospitals. Apixaban or rivaroxaban concentrations were measured after the first visit, regardless of last intake in obese patients receiving DOAC for VTE. Concentrations were compared to published reference values for non-obese patients. Demographic, clinical, biological and therapeutic data were collected. Univariate and multivariate analyses were performed to identify factors associated to DOAC concentrations outside the on-therapy ranges. RESULTS: Out of the 146 patients included, 22 (15%) had DOAC concentrations outside the on-therapy ranges, mainly in the rivaroxaban group (n = 17). Age ≤ 63 years, use of rivaroxaban and time since last intake ≤8 h were associated with DOAC concentrations outside the on-therapy ranges, in multivariable analysis. During the median follow-up of 16 months, two (1%) patients receiving apixaban had recurrent VTE. No patient had major bleeding, 11 (8%) patients had minor bleeding. CONCLUSION: In this specific prospective bi-centric study dedicated to VTE obese patients, use of DOACs at fixed doses led to concentrations similar to those of non-obese patients in a high proportion of patients, without any effect of the BMI, and with risk-benefit profile comparable to non-obese patients.
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Preparaciones Farmacéuticas , Tromboembolia Venosa , Humanos , Persona de Mediana Edad , Obesidad/complicaciones , Estudios Prospectivos , Pirazoles , Piridonas , Rivaroxabán/uso terapéutico , Tromboembolia Venosa/tratamiento farmacológicoRESUMEN
BACKGROUND: to compare three existing screening algorithms of pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) with the results of a multidisciplinary team (MDT) meeting from a tertiary center. METHODS: we conducted a monocentric longitudinal study from 2015 to 2018. All patients with SSc according to LeRoy's classification were eligible. Patients were excluded in the case of missing data required by any of the three screening algorithms. The algorithms were applied for each patient at inclusion. Right heart catheterization (RHC) was performed based on the MDT decision. MDT members were all blinded from the results of the three algorithms regarding RHC recommendations. The RHC recommendations of each algorithm were compared with the MDT decision, and the impact on diagnosis and management was evaluated. RESULTS: 117 SSc patients were consecutively included in the study, and 99 had follow-up data over the three-year duration of the study (10 deaths). Among the 117 patients, the MDT suggested RHC for 16 patients (14%), DETECT algorithm for 28 (24%), ASIG for 48 (41%) and ESC/ERS 2015 for 20 (17%). Among the 16 patients who had RHC, SSc-PAH was diagnosed in seven. Among patients with an initial recommendation of RHC based on at least one algorithm but not according to the MDT meeting, no SSc-PAH was diagnosed during the three-year follow-up. Results were unchanged when the new 2018 definition of PAH was applied instead of the previous definition. CONCLUSION: a MDT approach appears interesting for the screening of SSc-PAH, with a significant reduction of RHC performed in comparison with dedicated algorithms. The specific relevance of a MDT for the management and follow-up of patients with RHC recommended by existing algorithms but with no PAH warrants further studies.
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Side effects of long-term oral corticosteroid therapy. Systemic corticosteroid therapy has been used for over 70 years, and is still the cornerstone of the treatment of many conditions, in particular systemic, autoimmune or inflammatory diseases. Side effects of corticosteroids are numerous, and for most of them well known by prescribers. Nonetheless, guidelines for the prevention of corticosteroids toxicity are scarce, and the implementation of protective measures by prescribers is heterogenous. Hence, corticosteroids related complications entail a significant morbidity, which, importantly, could be largely prevented. We conducted therefore a systematic literature, through the Medline database, the Cochrane database and the grey literature until January 2021. After recalling the history of the discovery of corticosteroid therapy and its main pharmacological properties, we present the various complications associated with long-term corticosteroid therapy, and discuss the relevance of the preventive measures that may be proposed in daily practice in the light of available scientific evidence. This work highlights the importance of multidisciplinary follow-up, but above all of a thorough screening of the risk factors of complications at treatment initiation, and of a repeated evaluation of the complications all along the treatment course, in order to reduce the significant burden of morbidity associated with long-term corticosteroid therapy and to improve patient quality of life.
Effets indésirables de la corticothérapie orale au long cours. La corticothérapie systémique est utilisée depuis plus de 70 ans et reste la pierre angulaire du traitement de nombreuses affections. Ses effets indésirables sont nombreux et, pour la plupart, bien connus. Pour autant, les recommandations concernant leur prévention sont parfois manquantes, et souvent hétérogènes, y compris dans leur mise en Åuvre par les prescripteurs. De ce fait, les complications induites par la corticothérapie sont à l'origine d'une morbidité importante, la plupart du temps évitables. Nous avons donc réalisé une revue systématique de la littérature, à travers les bases Medline, Cochrane et la littérature grise, jusqu'à janvier 2021. Après avoir rappelé l'histoire de la découverte de la corticothérapie et ses principales caractéristiques pharmacologiques, nous présentons les différentes complications associées à une corticothérapie au long cours et les mesures de prévention disponibles, en discutant leur efficacité et leur pertinence à la lumière des recommandations actuelles ou, à défaut, des dernières données scientifiques disponibles. Ce travail met en évidence l'importance du suivi multidisciplinaire des patients traités par corticothérapie systémique au long cours, mais surtout celle d'un dépistage préalable des facteurs associés à la survenue de complications et de réévaluations répétées de ces complications sous traitement, afin de diminuer le poids très important de la morbidité qui y est associée et ainsi d'améliorer la qualité de vie des patients.
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Corticoesteroides , Calidad de Vida , Corticoesteroides/efectos adversos , Glucocorticoides/efectos adversos , HumanosRESUMEN
PURPOSE: The SARS-CoV-2 infection can lead to a severe acute respiratory distress syndrome (ARDS) with prolonged mechanical ventilation and high mortality rate. Interestingly, COVID-19-associated ARDS share biological and clinical features with sepsis-associated immunosuppression since lymphopenia and acquired infections associated with late mortality are frequently encountered. Mechanisms responsible for COVID-19-associated lymphopenia need to be explored since they could be responsible for delayed virus clearance and increased mortality rate among intensive care unit (ICU) patients. METHODS: A series of 26 clinically annotated COVID-19 patients were analyzed by thorough phenotypic and functional investigations at days 0, 4, and 7 after ICU admission. RESULTS: We revealed that, in the absence of any difference in demographic parameters nor medical history between the two groups, ARDS patients presented with an increased number of myeloid-derived suppressor cells (MDSC) and a decreased number of CD8pos effector memory cell compared to patients hospitalized for COVID-19 moderate pneumonia. Interestingly, COVID-19-related MDSC expansion was directly correlated to lymphopenia and enhanced arginase activity. Lastly, T cell proliferative capacity in vitro was significantly reduced among COVID-19 patients and could be restored through arginine supplementation. CONCLUSIONS: The present study reports a critical role for MDSC in COVID-19-associated ARDS. Our findings open the possibility of arginine supplementation as an adjuvant therapy for these ICU patients, aiming to reduce immunosuppression and help virus clearance, thereby decreasing the duration of mechanical ventilation, nosocomial infection acquisition, and mortality.
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Arginina/metabolismo , COVID-19/complicaciones , Linfopenia/etiología , Células Supresoras de Origen Mieloide/fisiología , Síndrome de Dificultad Respiratoria/inmunología , SARS-CoV-2 , Anciano , Infección Hospitalaria/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/metabolismo , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVES: To evaluate the diagnostic value of hand ultrasound (US) in systemic sclerosis (SSc) and to explore its relevance within a combined diagnostic approach. METHODS: 224 patients with suspected SSc were consecutively included. They all had US evaluation assessing the presence of fibrotic tenosynovitis (fibrotic TS) and ulnar artery occlusion (UAO). The final diagnosis of SSc was based on the clinical evaluation of a board of experts independently of any pre-established classification criteria. RESULTS: 166 patients were finally diagnosed as SSc according to the experts as reference standard. 62 SSc and 8 non-SSc patients had UAO (uni or bilateral) (p=0.001). 23 SSc patients and 1 non-SSc patient had US fibrotic TS (p=0.007). A US SSc-pattern (presence of UAO and/or fibrotic TS) was reported in 73 SSc patients and 9 non-SSc patients (p<0.001). UAO had an area under ROC curve (AUC) for the diagnosis of SSc of 0.618 (95%CI 0.539- 0.697); with Se=0.373 (0.304-0.449) and Sp=0.862 (0.751-0.928). Fibrotic TS had an AUC of 0.561 (0.480-0.643); with Se=0.139 (0.094-0.199) and Sp=0.983 (0.909-0.997). The US-SSc pattern had a AUC of 0.641 (0.563- 0.695), with Se=0.440 (0.367-0.516) and Sp=0.845 (0.731-0.916). A scoring system including these US parameters and items from ACR/EULAR classification criteria had an AUC of 0.979 (0.962-0.996)) and allows the substitution of capillaroscopy by US parameters with similar performances. CONCLUSIONS: The use of hand US parameters may help to refine the diagnostic strategy of SSc and their inclusion in a combined diagnostic approach could be discussed.
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Esclerodermia Localizada , Esclerodermia Sistémica , Humanos , Angioscopía Microscópica , Arteria Cubital , UltrasonografíaRESUMEN
CONTEXT: Thoracic lymphadenopathy (LA) has been identified as a key prognostic factor in interstitial lung disease (ILD) of all-cause. Crystalline silica is a risk factor of systemic sclerosis (SSc). The association of a history of crystalline silica exposure with chest high-resolution computed tomography (HRCT) features and thoracic LA are still to be determined in SSc patients. OBJECTIVES: We performed an observational study to assess the association of lifetime exposure to silica, with chest HRCT characteristics in a population of SSc patients fulfilling the 2013 ACR/EULAR classification criteria for SSc. METHODS: A specific questionnaire based on a multidisciplinary approach was used to assess occupational and non-occupational exposure to silica in 100 consecutive SSc patients. Clinical characteristics and chest HRCT at diagnosis and at the latest visit were evaluated to assess the association of silica exposure with disease characteristics. RESULTS: 16% of the overall population and 58% of men had an occupation with specific high silica exposure. A higher silica exposure score was associated with the combination of mediastinal and hilar LA on HRCT (OR=8.09, 95%CI=2.01-32.52, P = 0.002). More than 12% of the patients had a combination of mediastinal and hilar LA on HRCT. This marker of silica exposure was predictive of worsening of pulmonary involvement in univariate analysis (OR=5.86, 95%CI=1.64-20.89, P = 0.007) and multivariate analysis (OR=4.57, 95%CI =1.12-18.60, P = 0.034). CONCLUSIONS: In patients with SSc, the combination of mediastinal and hilar LA on HRCT was associated with exposure to silica and was also significantly associated with a more severe evolution of ILD.
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Enfermedades Pulmonares Intersticiales , Esclerodermia Sistémica , Humanos , Enfermedades Pulmonares Intersticiales/inducido químicamente , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Masculino , Esclerodermia Sistémica/diagnóstico por imagen , Dióxido de Silicio/toxicidad , Tomografía Computarizada por Rayos XRESUMEN
Janus kinase (JAK) inhibitors (also termed Jakinibs) constitute a family of small drugs that target various isoforms of JAKs (JAK1, JAK2, JAK3 and/or tyrosine kinase 2 (Tyk2)). They exert anti-inflammatory properties linked, in part, to the modulation of the activation state of pro-inflammatory M1 macrophages. The exact impact of JAK inhibitors on a wider spectrum of activation states of macrophages is however still to be determined, especially in the context of disorders involving concomitant activation of pro-inflammatory M1 macrophages and profibrotic M2 macrophages. This is especially the case in autoimmune pulmonary fibrosis like scleroderma-associated interstitial lung disease (ILD), in which M1 and M2 macrophages play a key pathogenic role. In this study, we directly compared the anti-inflammatory and anti-fibrotic effects of three JAK inhibitors (ruxolitinib (JAK2/1 inhibitor); tofacitinib (JAK3/2 inhibitor) and itacitinib (JAK1 inhibitor)) on five different activation states of primary human monocyte-derived macrophages (MDM). These three JAK inhibitors exert anti-inflammatory properties towards macrophages, as demonstrated by the down-expression of key polarization markers (CD86, MHCII, TLR4) and the limited secretion of key pro-inflammatory cytokines (CXCL10, IL-6 and TNFα) in M1 macrophages activated by IFNγ and LPS or by IFNγ alone. We also highlighted that these JAK inhibitors can limit M2a activation of macrophages induced by IL-4 and IL-13, as notably demonstrated by the down-regulation of the M2a associated surface marker CD206 and of the secretion of CCL18. Moreover, these JAK inhibitors reduced the expression of markers such as CXCL13, MARCO and SOCS3 in alternatively activated macrophages induced by IL-10 and dexamethasone (M2c + dex) or IL-10 alone (M2c MDM). For all polarization states, Jakinibs with inhibitory properties over JAK2 had the highest effects, at both 1 µM or 0.1 µM. Based on these in vitro results, we also explored the effects of JAK2/1 inhibition by ruxolitinib in vivo, on mouse macrophages in a model of HOCl-induced ILD, that mimics scleroderma-associated ILD. In this model, we showed that ruxolitinib significantly prevented the upregulation of pro-inflammatory M1 markers (TNFα, CXCL10, NOS2) and pro-fibrotic M2 markers (Arg1 and Chi3L3). These results were associated with an improvement of skin and pulmonary involvement. Overall, our results suggest that the combined anti-inflammatory and anti-fibrotic properties of JAK2/1 inhibitors could be relevant to target lung macrophages in autoimmune and inflammatory pulmonary disorders that have no efficient disease modifying drugs to date.
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Antiinflamatorios/farmacología , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Piperidinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Pirimidinas/farmacología , Pirroles/farmacología , Esclerodermia Sistémica/tratamiento farmacológico , Animales , Diferenciación Celular , Quimiocina CXCL13/genética , Quimiocina CXCL13/inmunología , Femenino , Regulación de la Expresión Génica , Ácido Hipocloroso/administración & dosificación , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 1/genética , Janus Quinasa 1/inmunología , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/genética , Janus Quinasa 2/inmunología , Janus Quinasa 3/antagonistas & inhibidores , Janus Quinasa 3/genética , Janus Quinasa 3/inmunología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Enfermedades Pulmonares Intersticiales/inducido químicamente , Enfermedades Pulmonares Intersticiales/inmunología , Enfermedades Pulmonares Intersticiales/patología , Activación de Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Nitrilos , Cultivo Primario de Células , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , Esclerodermia Sistémica/inducido químicamente , Esclerodermia Sistémica/inmunología , Esclerodermia Sistémica/patología , Proteína 3 Supresora de la Señalización de Citocinas/genética , Proteína 3 Supresora de la Señalización de Citocinas/inmunologíaRESUMEN
Inhalation of crystalline silica (SiO2) is a risk factor of systemic autoimmune diseases such as systemic sclerosis (SSc) and fibrotic pulmonary disorders such as silicosis. A defect of apoptotic cell clearance (i.e., efferocytosis, a key process in the resolution of inflammation) is reported in macrophages from patients with fibrotic or autoimmune diseases. However, the precise links between SiO2 exposure and efferocytosis impairment remain to be determined. Answering to this question may help to better link innate immunity and fibrosis. In this study, we first aim to determine whether SiO2 might alter efferocytosis capacities of human and mouse macrophages. We secondly explore possible mechanisms explaining efferocytosis impairment, with a specific focus on macrophage polarization and on the RhoA/ROCK pathway, a key regulator of cytoskeleton remodeling and phagocytosis. Human monocyte-derived macrophages (MDM) and C57BL/6J mice exposed to SiO2 and to CFSE-positive apoptotic Jurkat cells were analyzed by flow cytometry to determine their efferocytosis index (EI). The effects of ROCK inhibitors (Y27632 and Fasudil) on EI of SiO2-exposed MDM and MDM from SSc patients were evaluated in vitro. Our results demonstrated that SiO2 significantly decreased EI of human MDM in vitro and mouse alveolar macrophages in vivo. In human MDM, this SiO2-associated impairment of efferocytosis, required the expression of the membrane receptor SR-B1 and was associated with a decreased expression of M2 polarization markers (CD206, CD204, and CD163). F-actin staining, RhoA activation and impairment of efferocytosis, all induced by SiO2, were reversed by ROCK inhibitors. Moreover, the EI of MDM from SSc patients was similar to the EI of in vitro- SiO2-exposed MDM and Y27632 significantly increased SSc MDM efferocytosis capacities, suggesting a likewise activation of the RhoA/ROCK pathway in SSc. Altogether, our results demonstrate that SiO2 exposure may contribute to the impairment of efferocytosis capacities of mouse and human macrophages but also of MDM in SiO2-associated autoimmune diseases and fibrotic disorders such as SSc; in this context, the silica/RhoA/ROCK pathway may constitute a relevant therapeutic target.