Urinary soluble VCAM-1 in systemic lupus erythematosus: a clinical marker for monitoring disease activity and damage.

OBJECTIVE

To determine the urinary levels of soluble vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in patients with systemic lupus erythematosus (SLE) and to assess their relationship with clinical and laboratory features and the degree of activity and damage associated with the disease.

METHODS

The study sample included 24 consecutive patients with SLE. 24-hour urine samples were collected for the determination of soluble VCAM-1 and ICAM-1 levels by ELISA. Disease activity was defined by the SLE Disease Active Index (SLEDAI) and disease outcome by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ ACR) damage index.

RESULTS

The urinary soluble VCAM-1 level was significantly higher in patients with SLE compared to normal controls (32.35+/-34.27 vs. 4.66+/-3.8 ng/mg creatinine, p = 0.0005) and statistically significantly correlated with disease activity (SLEDAI), a low serum C3 level, decreased creatinine clearance and albuminuria, as well as with disease damage (SLICC/ACR damage index). In contrast, the urinary soluble ICAM-1 level was not significantly higher in the patients' group compared with the controls (4.5+/-5.19 vs. 2.72+/-2.31 ng/mg creatinine, p=0.2), but was statistically significantly correlated with hematuria and albuminuria.

CONCLUSION

Our data suggest that the urinary level of soluble VCAM-1 significantly correlates with overall disease activity and damage scores, but not with nephritis in SLE.