Introduction. The incidence of respiratory system involvement in patients with rheumatoid arthritis (RA) has currently increased; thereby new diagnostic methods have been developed actively. Meanwhile role of vascular disorders in pathogenesis of lung injury is almost unknown and single-photon emission computed tomography (SPECT) isn't used as method of lung assessment in RA. The detector of endothelial glycocalyx damage syndecan-1 is little known but potentially perspective serum marker of lung injury in RA. Objective. The purpose of the study was to investigate the role of vascular disorders in lung injury in patients with RA. Materials and methods. 61 patients with RA without comorbid lung diseases were enrolled in the study. Control group consisted of 26 healthy persons. Patients underwent survey and physical examination, high-resolution computed tomography (HRCT) and SPECT of the lungs and pulmonary function tests (PFTs). Also serum levels of rheumatoid factor (RF), anti-cyclic citrullinated peptide antibodies (ACCP) and syndecan-1 were measured. Results. All patients developed microcirculation impairment on SPECT. Vascular disorders were according to changes of lung structure detected by HRCT (r = 0.434; p = 0.044). Areas of hypoperfusion matched with ground glass opacities, lung fibrosis, branching linear structures and airway obstruction on HRCT-SPECT fusion scans. Syndecan-1 level was higher in patients with RA compared with healthy controls (р = 0.019). Conclusion. Vascular disorders are important in pathogenesis of lung injury in RA, and SPECT has high sensitivity in lung assessment. Perfusion impairment in lungs correlates with syndecan-1 level, thus syndecan-1 could be used as marker of lung injury in RA thereafter.

BackgroundBronchial obstruction (BO) is a common manifestation of lung involvement in rheumatoid arthritis (RA) with high incidence from 60 to 80% of all cases. However the pathogenesis of BO in patients with RA remains unknown. Serum level of protein CC16 produced by Clara cells in terminal bronchioles has been reported to decrease in BO associated with bronchial asthma, chronic obstructive pulmonary disease and others. CC16 was considered to demonstrate anti-inflammatory effect via inhibition of interferon-gamma, tumor necrosis factor alpha, interleukin 1 beta, neutrophil elastase and other proinflammatory factors. Also it was shown that CC16 deficiency has a pathogenic effect in BO. In the same time the role of protein CC16 in the pathogenesis of autoimmune diseases (and RA) is not studied.ObjectivesWe aimed to evaluate serum level of CC16 in patients with RA in dependence on the presence and severity of BO.MethodsSerum levels of CC16 in 66 patients with RA and 13 healthy controls were measured by enzyme linked immunoadsorbent assay (ELISA). Patients with RA underwent survey, physical examination and pulmonary function tests (PFTs) including spirometry and bronchodilator test with inhalation of salbutamol (N=41) and body plethysmography (N=11). Statistical processing was carried out using Spearman correlation coefficient and Mann-Whitney test. P value <0.05 was considered as significant.ResultsMore than 60% of participants with RA had BO in terminal bronchioles (small airway obstruction), which was revealed with changes of expiratory flows (forced expiratory volume in 1s (FEV1), forced expiratory flow (FEF) between 50% and 75% of forced vital capacity), residual volume (RV) and bronchial resistance (SGaw) in relation to proper values. Depression of post-bronchodilator FEF75% lower than 70% was adopted as the main criterion of BO. There were no differences (p value >0,05) between serum levels of CC16 in patients with RA (20,14±1,49 ng/ml) and control group (22,70±2,13 ng/ml). However in patient group those with BO had significantly lower levels of CC16 (15,59±1,89 compared with 27,43±2,81 in patients without BO, p value <0,01). Lower CC16 was associated with decreased post-bronchodilator FEV1 and FEF75% (r =0,345, p value <0,05 and r =0,486, p value <0,01 respectively), depressed bronchial resistance SGaw (r =0,773, p value <0,01) and increased RV (r = -0,736, p value <0,01), which determined BO severity.ConclusionsMore than half of patients with RA have BO predominantly in terminal bronchioles. Accepting significant decrease of Clara cell protein CC16 in patients with RA having BO we suppose pathogenic relationship between functional depression of Clara cell anti-inflammatory activity and BO in this category of patients.References Park HY. Club cell protein 16 and disease progression in chronic obstructive pulmonary disease (2013). Disclosure of InterestNone declared

Introduction. Rheumatoid arthritis (RA) affects not only the joints but also other organs. Lung disease is one of the leading manifestations of RA, and detection of these changes remains a diagnostic challenge. Delayed diagnosis of pulmonary involvement in the pathogenesis of RA often leads to development of severe forms which aggravate prognosis and decrease of the quality of life. Identify the characteristics and prognostic significance of CT and SPECT symptoms involving respiratory system in patients with RA depending on the stage of the disease and the destruction of hand joints as detected by MRI. Methods. To evaluate favorable and unfavorable predictors of RA clinical course and detect changes in the lung using modern methods of imaging: magnetic resonance, computed tomography and single-photon emission computed tomography. Results. A set of signs identified by CT and SPECT was analyzed corresponding to the presence of different types of erosions detected by MRI. Pleural adhesions, symptoms of bronchial obstruction (uneven ventilation, «air trap»), and signs of vasculitis were observed in all stages of the disease. With the progression of the disease, bullous emphysema-type deforming bronchitis symptoms and associated comorbid processes in the lung tissue were observed. Conclusions. For all types of active RA in patients with a high frequency revealed signs of bronchial obstruction and concomitant manifestations of vasculitis. These results require the inclusion of X-ray and single photon emission computed tomography of the chest in the algorithm of diagnostic evaluation of the patients with RA to identify and assess changes related primarily to the blood circulation, have prognostic significance and impact on treatment regimen.