To observe the clinical feature of rheumatoid arthritis associated interstitial lung disease (RA-ILD) patients and changes of serum cytokines tumor growth factor (TGF)-beta 1, tumor necrosis factor (TNF)-alpha, insulin-like growth factor (IGF)-1, and platelet derived growth factor (PDGF)-AB.
The clinical manifestations, lung high resolution CT (HRCT), lung functions, blood gas and other relative laboratory findings of 30 RA-ILD patients and 35 RA patients were observed. ELISA was used to detect the levels of TGF-beta 1, TNF-alpha, IGF-1, and PDGF-AB. Thirty healthy volunteers were observed too as controls.
The clinical manifestations of RA-ILD patients were more serious than those of the RA patients. The ESR was faster, the serum C-reactive protein, rheumatoid factor (RF), and globulin levels higher, and pulmonary arterial pressure higher too in the RA-ILD patients than in the RA patients (all P<0.01). The main respiratory manifestations of the RA-ILD patients were cough, expectoration, chest distress, short breath, chest pain, change of breath sounds, Velcro râles, and dyspnea. The main lung HRCT findings included thickening of interlobular septum and bronchial wall, pachynsis pleurae, mosaic sign, bronchiectasis, emphysema, patching shadow, honeycombing, fibrous scar, etc. Pulmonary function test showed that the levels of vital capacity, forced vital capacity, maximum midexpiratory flow, and diffusing capacity of the lung for carbon monoxide of the RA-ILD patients were all significantly lower than those of the RA patients (all P<0.01). Arterial gas test showed that the PO2 of the RA-ILD patients was significantly lower than that of the RA patients (P<0.01). The TGF-beta 1; TNF-alpha, IGF-1, and PDGF-AB of both the RA-ILD and RA patients were all significantly higher than those of the healthy volunteers (all P<0.01), and the levels of these cytokines of the RA-ILD patients were all higher than those of the RA patients (all P<0.01).
The symptoms and signs of the RA-ILD patients are more serious, the lung HRCT changes more obvious, lung function decreases, and the levels of TGF-beta 1, TNF-alpha, IGF-1, and PDGF-AB increase.