Background/Purpose:

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown etiology, characterized by a broad spectrum of clinical manifestations. There is a large variety of nail abnormalities described in SLE; these abnormalities were detected with a frequency of 25-31% in different series of patients with SLE. Although nail changes have been rarely considered a specific sign of the disease, they have been associated with an increased disease activity, higher incidence of Raynaud’s phenomenon and oral ulcerations. It has been postulated that vascular damage plays a crucial role in the pathogenesis of SLE, so many studies have focused on the role of angiogenesis activity markers and endothelial damage. We suggest that the nail dystrophy (ND) could be a reflection of the damage to the microvasculature in patients with SLE.

Objectives: To evaluate the possible association between nail dystrophy (ND) and disease activity, damage index, capillaroscopic abnormalities, autoantibody profile, and endothelial cell activation markers in systemic lupus erythematosus (SLE).

Methods:

Analytical and transversal study of SLE patients from a Rheumatology Clinic in a tertiary care hospital. The patients have been divided in two groups, one with, and the other without ND (control group). Clinical, demographic, activity, chronicity, serologic, nailfold capillaroscopy (NFC) characteristics, serum levels of anti-endothelial cell antibodies (AECA), and plasma levels of endothelin-1 (ET-1), were compared between groups.  Activity was determined by the SLEDAI-2K and damage by the SLICC/ACR Damage Index. The AECA and ET-1 were determined by an enzyme-linked immunosorbent assay (ELISA).

The probability of differences in the variables frequency distributions was determined by χ² test, and the significance of the differences between the means was determined using Mann-Whitney test.  P-values less than 0.05 were considered statistically significant. The unpaired t-test was used to assess differences between SLE subgroups.

Results:

Sixty one patients were included; 50 (82%) were female. Thirty two (52.5%) patients showed ND and 29 did not (control group). The sex, mean age and disease duration were similar in both groups. A significant association of ND with an increased damage index was found (p=0.04). Cyclophosphamide was more used in the ND group (p=0.03). Onycholysis was the most frequently nail change, it was reported in 40% of the patients. NFC changes were detected in 43% of the ND patients and in 13% of the controls (p=0.02). The most frequent NFC finding in the ND group was elongated capillaries (40%). There was not an association of autoantibody profile, ET-1, and AECA with ND.

Conclusion:

ND is associated with a greater index of chronicity and with capillaroscopic abnormalities. This might suggest that ND is caused by microvascular damage.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/association-of-nail-dystrophy-with-capillaroscopic-abnormalities-anti-endothelial-cell-antibody-endothelin-1-activity-and-chronicity-in-systemic-lupus-erythematosus/