Systemic sclerosis sine scleroderma and limited cutaneous systemic sclerosis: similarities and differences

Area of Science:

• Rheumatology
• Immunology
• Internal Medicine

Background:

• Systemic sclerosis (SSc) is a complex autoimmune disease characterized by fibrosis, vasculopathy, and immune dysregulation.
• Distinguishing between subtypes like systemic sclerosis sine scleroderma (ssSSc) and limited cutaneous systemic sclerosis (lcSSc) is clinically important for patient management.
• Understanding the distinct clinical and immunological profiles of SSc subsets aids in accurate diagnosis and prognosis.

Purpose of the Study:

• To compare the demographic, clinical, immunological, and survival characteristics of patients with systemic sclerosis sine scleroderma (ssSSc) versus limited cutaneous systemic sclerosis (lcSSc).
• To identify key differences and similarities between ssSSc and lcSSc to inform diagnostic strategies.
• To evaluate the necessity of considering ssSSc as a distinct subset of systemic sclerosis.

Main Methods:

• A comparative cohort study involving 45 patients with ssSSc and 186 patients with lcSSc.
• Investigation included demographic data, clinical manifestations, immunological markers, and patient survival.
• Statistical analysis was performed to compare features between the two groups.

Main Results:

• No significant differences were observed in gender, age at onset, or time to diagnosis between ssSSc and lcSSc.
• ssSSc patients less frequently met ACR criteria for SSc (13% vs. 77%). Peripheral vascular manifestations like digital ulcers and calcinosis were more common in lcSSc.
• Survival rates were similar between ssSSc and lcSSc groups at 5, 10, and 15 years, despite a trend towards higher pulmonary arterial hypertension in ssSSc.

Conclusions:

• Systemic sclerosis sine scleroderma and limited cutaneous systemic sclerosis patients share significant demographic, clinical, and immunological features, with comparable survival rates.
• Key differences lie primarily in peripheral vascular involvement, with lcSSc exhibiting a higher prevalence of digital ulcers and calcinosis.
• Despite similarities, ssSSc should be recognized as a distinct subset to prevent misdiagnosis, necessitating sensitive studies for early, potentially asymptomatic organ involvement.