Comparison of serum ferritin level in patients with systemic lupus erythematosus, rheumatoid arthritis and osteoarthritis

Background: Systemic Lupus Erytematosus (SLE) is a chronic and relapsing disorder affecting several organs. Objective: To compare serum ferritin level between patients with systemic lupus erythematosus, rheumatoid arthritis, and osteoarthritis Methods: This cross-sectional study was conducted on 60 patients with SLE (divided into two groups with low and high disease activity), 20 patients with osteoarthritis (OA), and 20 patients with rheumatoid arthritis (RA). After having received informed consent, the blood and urine samples were collected from all patients to be tested for iron, TIBC, and serum ferritin levels and also to calculate the lupus disease activity. Patients with iron deficiency anemia were excluded. Data were analyzes by independent t- test, ANOVA, logistic regression and correlation tests. Findings: There was no significant difference between three study groups regarding the sex however, the age and duration of disease showed significant differences among 3 groups (p< 0.001). High serum ferritin level was seen in 61.7% of SLE, 15% of RA, and 5% of OA patients (p< 0.001). Increase in ESR levels demonstrated significant differences among study groups (p< 0/001). In patients with SLE, no significant correlation between serum ferritin and the decreased serum complement level and increased anti dsDNA titer was observed. Both serum ferritin and CRP levels increased in patients with serositis (p=0.019) and neurological complication (p=0.04). Conclusion: Serum ferritin level was significantly higher in patients with SLE compared to those with OA and RA. There was no significant difference between serum ferritin level and SLE activity.