Fibrotic Cytokine Interplay in Evaluation of Disease Activity in Treatment Naïve Systemic Sclerosis Patients from Western India.

BACKGROUND: : Systemic sclerosis (SSc) is a demyelinating disease of skin, subcutaneous tissue, muscles and internal organs, with fibrosis as an important pathological event. AIM: : To understand cytokine interplay of IL-1ß, IL-4 and IL-6 and their association with disease activity in treatment naïve active cases of systemic sclerosis from Western India. METHODS: Twenty-five SSc patients as per ACR-EULAR 2013 criteria (classified based on pulmonary fibrosis and generalized fibrosis) and 25 age-sex matched controls were enrolled. Serum cytokine levels of IL-1ß, IL-4 and IL-6 were assessed by multiplex bead based immunoassay. RESULTS: Ten patients had Interstitial lung disease (ILD), whereas, 16 patients had generalized fibrosis. Anti-nuclear antibodies were seen in 22 patients (88%); antiScl70 in 15 patients (60%) and anti-Centromere antibodies in 5 patients (20%). Serum levels of IL-1ß in patients were significantly higher than healthy controls (p=0.0006). IL-4 levels in all SSc patients were marginally raised (p=0.0102), while IL-6 levels were significantly raised (p<0.0001). IL-4 was found to be significantly raised in SSc patients with ILD (p=0.021) as compared to patients without ILD. IL-1ß (p=0.0293) and IL-4 (p<0.0001) were significantly higher in SSc patients with fibrosis. On the contrary, IL-6 levels in patients with fibrosis were found to be lower than in patients without fibrosis. CONCLUSION: Significantly raised cytokine levels among treatment naïve systemic sclerosis patients were found to be associated with higher disease severity in our study. Higher levels of IL-1ß and IL-6 indicated an active inflammatory status, whereas significantly raised IL-4 levels indicated at higher fibrotic activity.