1980 Criteria for the Classification of Systemic Sclerosis

The American College of Rheumatology (former American Rheumatism Association - ARA) has defined criteria, that are 97 % sensitive and 98 % specific for systemic sclerosis (SSc) as follows:

Major criterion:

• Proximal diffuse (truncal) sclerosis (skin tightness, thickening, non-pitting induration)

Minor criteria:

• Sclerodactyly (only fingers and/or toes)

• Digital pitting scars or loss of substance of the digital finger pads (pulp loss)

• Bilateral basilar pulmonary fibrosis

The patient should fulfill the major criterion or two of the three minor criteria. Raynaud's phenomenon is observed in 90-98 % of SSc patients.

Subsets of Systemic Sclerosis

	Diffuse	Limited*
Skin involvement	Distal and proximal extremities, face, trunk	Distal to elbows, face
Raynaud’s phenomenon	Onset within 1 year or at time of skin changes	May precede skin disease by years
Organ involvement	Pulmonary (interstitial fibrosis); renal (renovascular hypertensive crisis); gastrointestinal; cardiac	Gastrointestinal; pulmonary arterial hypertension after 10-15 years of disease in <10% of patients; biliary cirrhosis
Nail fold capillaries	Dilatation and dropout	Dilatation without significant dropout
Antinuclear antibodies	Anti-topoisomerase 1	Anticentromere

* Also referred to as CREST( calcinosis, Raynaud’s, esophageal dysmotility, sclerodactyly, telangiectasia).

 

ABCDCREST Criteria for the Classification of Systemic Sclerosis

1. Autoantibodies: autoantibodies to centromere proteins (CENPs) detected by indirect immunofluorescence; anti-Scl-70 (topoisomerase I) detected by double immunodiffusion; anti-fibrillarin (U3-RNP) detected by immunoprecipitation

2. Bibasilar pulmonary fibrosis detected by chest radiograph: linear shadows or “honey-comb” reticular appearance most expressed at the periphery of the lungs and at the bases

3. Contracture of the joints defined as permanent limitation of joint motion. The prayer sign is detected when a patient opposed the palmar surfaces of both hands with extended wrists. The sign is positive when the patient is unable to oppose the palms. This suggests joint or skin pathology, or shortening of the forearm flexors

4. Dermal thickening can be defined by the modified Rodnan skin score, which employs clinical palpation of the skin as described

5. Calcinosis cutis, most often located on the fingers, is intra and/or subcutaneous deposits of hydroxyapatite that can ulcerate the skin; it can be detected by radiography, crystallographic or chemical analysis

6. Raynaud’s phenomenon is a sudden pallor of an acral structure (e.g., fingers, whole hand, toes, tip of nose, earlobe, or tongue). The involved area may subsequently develop cyanosis and, with re-warming, become erythematous. Determination is by patient’s history or physician’s observation

7. Esophageal distal hypomotility can be detected by cine/video barium esophagram, performed in the upright and supine position. Reflux-esophagitis can be detected by esophagogastroduodenoscopy in the forms of erosive esophagitis or Barret’s esophagus

8. Sclerodactyly is symmetric thickening and tightening of the skin on the digits. Before sclerodactyly develops there could be a phase of non-pitting digital edema of varying duration. It is defined as non-pitting increase in soft tissue mass of the digits that extends beyond the normal confines of the joint capsules

9. Teleangiectasias are visible macular dilatations of superficial cutaneous blood vessels that collapse upon pressure and fill slowly when pressure is released. Common locations are the digits, face, lips, tongue

A classification of definite SSc requires three or more criteria.