Serum concentrations of cyclooxygenase-2 in patients with systemic sclerosis: association with lower frequency of pulmonary fibrosis.

Systemic sclerosis (SSc) is a multisystem disease in which interplay between inflammation, autoimmunity and fibrosis appears to play an indispensable role. Owing to the suggested role of cyclooxygenase-2 enzymes (Cox-2) in inflammation and fibrosis, we investigated their serum concentrations in SSc patients and their clinical and laboratory associations. Serum from 49 patients with SSc, 28 of whom had limited cutaneous SSc (lSSc) and 21 had diffuse cutaneous SSc (dSSc) subtypes, and from 27 healthy subjects were assayed for Cox-2 and TNF by enzyme-linked immunosorbent assay (ELISA). Demographic, clinical, autoantibodies and serological data were prospectively assessed. The analysis revealed that patients with lSSc had higher levels of serum Cox-2 than controls. Serum Cox-2 levels were increased in SSc patients with arthritis and digital ulcers; on the contrary, these were diminished in those with associated pulmonary fibrosis. An additional prospective large scale, longitudinal study should be carried out to support these findings and to reveal the mechanistic connections between Cox-2 levels and SSc disease manifestations.