C-reactive protein levels tend to rise significantly during active infections; whereas in the setting of a lupus relapse, elevation is usually mild or absent.12,13 However, this increase during infections may be attenuated in immunocompromised patients, especially in those on treatment with corticosteroids.14 On the other hand, elevated CRP levels can also be found in SLE patients with active serositis or synovitis and no evidence of infection, thus making CRP a marker with low diagnostic specificity.15–17. This evidence concerns the gene CRP and synovitis.