β2-microglobulin as a marker of systemic lupus erythematosus activity

Systemic lupus erythematosus (SLE) is characterized by alternating periods of activity and remission. A portion of the patients suffers from the chronically active form of the disease. The search for clinically useful markers of its activity is ongoing. At present, it is suggested that β2-microglobulin (β2M) may be useful in assessing SLE activity.

The objective of the paper was to investigate the relationship between serum β2M concentration and SLE activity.

The study group consisted of 69 SLE patients (62 women and 7 men), aged 34.5 ±11 years (19-69). Patients with kidney failure and infection were excluded from the study group. The concentration of β2M was measured using an ELISA test. SLE activity was assessed with Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K), and by measuring the levels of C3 and C4 complement components, anti-double stranded DNA antibodies (anti-dsDNA antibodies) and β2M. The relationship between β2M and the clinical manifestation of SLE was also covered in the study.

The study revealed a statistically significant correlation between β2M concentration and SLEDAI-2K disease activity index (p < 0.05; r = 0.6), anti-dsDNA titer (p < 0.05; r = 0.3), and C4 component serum level (p < 0.05; r = -0.3). β2M concentration was significantly higher in patients with arthritis and/or myositis (p = 0.005), vasculitis (p = 0.005), and hematological manifestations of SLE (p = 0.02).

Periodical determination of β2M concentration in SLE patients may prove helpful in assessing the disease activity.