Systemic sclerosis: demographic, clinical and serological features in 100 Iranian patients

Abstract

To evaluate demographic, clinical and laboratory features associated with scleroderma-specific auto-antibodies. Sera of 100 patients with systemic sclerosis (SSc) were analyzed by an indirect immunofluorescence technique with HEp-2 cells as a substrate. Specific ANA such as anti-centromere antibodies (ACA), anti-topoisomerase (TOPO), anti-RNA polymerase III (Pol 3), anti-U3-RNP (U3-RNP), anti-Th/To (Th/To) and anti-PM/Scl (PM/Scl) were detected by line immunoassay and anti-U1-RNP (U1-RNP) by ELISA. Frequency of clinical features associated with a specific antibody group was reported cumulatively over the follow-up period. Frequency of specific clinical features was compared across the two disease subtype including limited cutaneous (lcSSc) or diffuse cutaneous (dcSSc) as well as the auto-antibody groups. Ninety-four percent of patients were ANA positive with significant higher skin score, Raynauds and digital ulcer/gangrene. Anti-TOPO was detected in 71% of all patients, in 90.5% of dcSSC and in 65.8% of lcSSc. Anti-TOPO was significantly associated with dcSSc, higher skin score, digital ulcer/gangrene, pulmonary fibrosis, DLCO <70%. U1-RNP antibody was associated with lower fibrosis in lung. ACA was positive in 7% of patients and exclusively in those with lcSSc. We did not find association between gender and presence of auto-antibodies. Anti-TOPO antibody had a high prevalence in contrast to low prevalence of ACA antibody. There were no differences in clinical subtypes of the disease in patients with positive anti-TOPO and positive ACA. Differences in prevalence of auto-antibodies are suggestive of further genetic study.

Clinical differences between Thai systemic sclerosis patients with positive versus negative anti‐topoisomerase I

“…According to our analysis, ATA was not associated with pulmonary fibrosis, which was the most common clinical feature associated with being ATA positive in most studies; rather it was associated with a short time for developing pulmonary fibrosis in the dcSSc subset. We therefore suggest close monitoring for pulmonary involvement, particularly in early‐onset disease for all sufferers of the dcSSc subset positive for ATA, in order to: (i) prevent extensive progression of lung fibrosis; and (ii) begin breathing exercises as early as possible.…”

“…Anti‐topoisomerase I antibody is a specific antibody for SSc, strongly associated with the dcSSc subset . However, it was not as strongly associated with a SSc subset among our patients after multivariate analysis.…”

Relevance of clinical and autoantibody profiles in systemic sclerosis among Thais

“…Notwithstanding, the prevalence and clinical association of these antibodies depend on reports of various studies. For example, ATA is reported as being between 18 and 85% [4][5][6][7][8][9] and associated with dcSSc, 5,10 pulmonary fibrosis, 5,8,10 cardiac involvement, 5 digital ulcer, 10 hand deformity, 4 a short duration of pulmonary fibrosis in dcSSc 4 and a lower frequency of Raynaud's phenomenon (RP) in lcSSc. 4 By comparison, ACA is reported as being between 7% and 40% 4,11,12 and associated with lcSSc 12 and pulmonary arterial hypertension 5 and having a negative association with pulmonary fibrosis and cardiac involvement.…”

Antinuclear antibodies in systemic sclerosis associated with increased risk of malignancy

“…Przeciwciała przeciw topoizomerazie I wykrywa się u 9,4-71% pacjentów z SSc i wykazują one wysoką swoistość dla SSc [28]. Antygenem dla tych przeciwciał jest enzym o masie 70 kDa, który bierze udział w replikacji DNA [29].…”

“…Anti-topoisomerase I antibodies (anti-TOPO I) may be detected in 9.4-71% of patients with SSc and are highly specific for SSc [28]. The antigen for these antibodies is a 70 kDa enzyme involved in DNA replication [29].…”