Carbohydrate-deficient transferrin depends on disease activity in rheumatoid arthritis and systemic sclerosis.

Objectives: Changes in the glycosylation of plasma proteins have been linked to the aetiology of the rheumatic diseases. The aim of this study was to determine and compare the levels of carbohydrate-deficient transferrin (CDT) in patients with rheumatoid arthritis (RA), systemic sclerosis (SSc), and systemic lupus erythematosus (SLE).

Method: Studies were carried out in 29 female patients with RA, 27 with SSc, and 17 with SLE. CDT was assayed by the N Latex CDT immunonephelometric assay.

Results: The levels of %CDT in the sera of RA, SLE, and SSc patients were significantly higher than in controls while the absolute concentrations of CDT were unchanged. %CDT, CDT, and transferrin do not differ significantly between patients with rheumatic diseases. In RA and SSc patients, a positive correlation was observed between %CDT and C-reactive protein (CRP), as well as a positive correlation in RA patients between %CDT and 28-joint Disease Activity Score (DAS28).

Conclusions: The changes in the serum %CDT concentration in patients with RA and SSc correlated with disease activity markers.