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

: Systemic sclerosis (SSc) is a demyelinating disease of skin, subcutaneous tissue, muscles and internal organs, with fibrosis as an important pathological event.

: To understand cytokine interplay of IL-1β, IL-4 and IL-6 and their association with disease activity in treatment naïve active cases of systemic sclerosis from Western India.

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-1β, IL-4 and IL-6 were assessed by multiplex bead based immunoassay.

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-1β 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-1β (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.

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-1β and IL-6 indicated an active inflammatory status, whereas significantly raised IL-4 levels indicated at higher fibrotic activity.