December 12/13: New Classification Criteria for Systemic Sclerosis
- The new classification system gives improved sensitivity and specificity for systemic sclerosis
- It allows inclusion in clinical studies of patients with early SSc and/or limited cutaneous disease
van den Hoogen F, Khanna D, Fransen J et al
2013 Classification Criteria for Systemic Sclerosis
Arthritis Rheum 2013; 65: 2737–2747
Background: The American College of Rheumatology (ACR) classification for systemic sclerosis (SSc) was developed using patients with longstanding SSc and has stood for 30 years despite being recognised as lacking sensitivity for early SSc and limited cutaneous SSc. Because of advances in knowledge about SSc, the ACR and the European League Against Rheumatism (EULAR) formed a consensus group to develop new classification criteria for SSc.
Summary: The proposed system was constructed by looking at 23 candidate items and reducing these to the most relevant. It was then tested by determining sensitivity and specificity in defined patients and in controls with scleroderma-like disorders and by validating against an expert panel opinion. Skin thickening of the fingers of both hands extending proximal to the metacarpophalangeal joints is sufficient for the patient to be classified as having SSc; if that is not given, 7 additional items (and sub-items) apply with varying weighting for each:
- Skin thickening of the fingers
- Fingertip lesions
- Abnormal nail fold capillaries
- Interstitial lung disease or pulmonary arterial hypertension
- Raynaud’s phenomenon
- Presence of SSc-related autoantibodies
Conclusions: The workgroup has developed a set of criteria for use by rheumatologists, researchers, national and international drug agencies, pharmaceutical companies and any others involved in studies of SSc. The classification system enables identification of individuals with SSc for inclusion in clinical studies and is more sensitive and specific than the previous one.
Comment: This timely and well-considered classification update offers greater sensitivity and clarification to clinicians and researchers working with SSc and will be welcomed by these groups and their patients.