Interstitial lung disease in South Africans with systemic sclerosis

Area of Science:

• Rheumatology
• Pulmonology
• Immunology

Background:

• Systemic sclerosis (SSc) is a multisystem autoimmune disease characterized by fibrosis of the skin and internal organs.
• Interstitial lung disease (ILD) is a major cause of morbidity and mortality in SSc patients.
• Data on the frequency, severity, and predictors of ILD in South African SSc cohorts are limited.

Purpose of the Study:

• To determine the prevalence, severity, and risk factors for ILD in a South African cohort of patients with SSc.
• To identify clinical and serological predictors associated with the development of ILD in SSc.
• To evaluate the prognosis and mortality related to ILD in this specific population.

Main Methods:

• Retrospective review of medical records of 151 SSc patients attending a tertiary Connective Tissue Diseases Clinic.
• Patients were categorized based on the presence or absence of ILD, defined by clinical, imaging, and pulmonary function tests.
• Demographic data, clinical manifestations, and autoantibody profiles were compared between ILD and non-ILD groups.

Main Results:

• 40% of the 151 SSc patients had ILD, with 39% experiencing moderate-to-severe lung disease.
• Univariate predictors of ILD included longer disease duration, cough, dyspnea, bibasal crackles, diffuse cutaneous SSc (dcSSc), and speckled anti-nuclear antibody (ANA) pattern.
• Independent predictors for ILD were bibasal crackles, disease duration, and speckled ANA. Limited cutaneous SSc and anti-centromere antibody (ACA) were protective.
• ILD was the leading cause of death (44.4%) in this cohort, and 86.4% received immunosuppressive treatment.

Conclusions:

• SSc-associated ILD is prevalent and associated with a poor prognosis in this predominantly Black South African cohort.
• ILD predominantly affects patients with dcSSc, particularly those with a speckled ANA pattern.
• The presence of ACA appears to be protective against ILD development in SSc.