1. Early Symptoms

The most common early symptoms of SSc are Raynaud’s phenomenon and insidious edematous skin changes of extremities and face. About 70% of the cases first present with Raynaud’s phenomenon, which appears either 1-2 years prior to or simultaneously with other manifestations. Polyarthral lesions are also prominent early manifestations. Patients may complain of irregular fever, appetite and weight loss before onset of symptoms.

2. Skin Changes

According to the skin changes, SSc can be divided into limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc), but the former is more common. These two types are different in the skin involvement area. Lesions of lcSSc begin in the areas of hands, feet and face, which are limited, progress slowly and have a good prognosis, while those of dcSSc are more diffused. Skin lesions may develop into three phases, named swelling, hardening and atrophy.

 (1) Swelling Phase

The skin is taut, thickened, with wrinkles disappearing, pale or light yellow, lower skin temperature and nonpitting edema. The skin lesions of lcSSc usually start from hands, feet and face, and spread into upper limbs, shoulders and neck. The lesions of dcSSc, however, can also be seen in body trunk.

 (2) Hardening phase

The skin gets hardened with a wax-like shine and cannot be pinched up by fingers. As the lesions occur in different areas, a variety of symptoms may be presented, such as restricted finger flexion, fixed facial expression, difficulties in opening mouth and closing eyes and chest tightness. In the involved skin, pigmentation, hypopigmentation and oligotrichosis can be seen. Besides, itchiness and paraesthesia may also happen at the same time.  

 (3) Atrophy phase

The skin undergoes parchment-like change of thinning and atrophy. In some cases, even the subcutaneous tissue and muscles are weakened and hardened, which tightly stick to the skeleton. Pitting scars are formed on extremities and usually cause intractable skin joints and ulcers. Hair loss and hypohidrosis can be seen. Few cases may present with telangiectasia.

The skin lesions above are the most prominent in all types of SSc. But it should be noted that some SSc remain asymptomatic in the skin.

3. Muscle Involvement

Muscle involvement is not rare. Abnormal electromyography is viewed in about 50% of the cases early in the disease. Clinical manifestations include myasthenia, diffuse myalgia and polymyositis-like symptoms in some cases. Severe involvement of muscle may advance into amyotrophy.

4. Skeleton and joint change

Inflammatory joint pain is not rare in initial stage, which occurs in 12% of the cases in their early manifestations and 46% in the overall course of the disease. Patients may have slight limit in range of movement, while severe cases shows ankylosis or even contracture and deformity of the joints. Hand involvement is most common, which can be measured as total stiffness, shortening in fingers and deformation. Chronic dactyl ischemia, however, may result in osteolysis in terminal phalanges, which can be viewed in X-ray. Other imaging findings include joint space narrowing, bone sclerosis adjacent to articular surface and osteoporosis.  

Visceral organ involvement is the critical feature to differ dcSSc from lcSSc:

(1) Gastrointestinal System

Tongue movement may be limited by contracture of the glossodesmus and apical root resorption causes loosening of the teeth. Esophageal involvement is quite common (45%-90%) and dysfunction of the lower esophageal sphincter may result in heartburn and sour regurgitation. If it lasts long, complications like erosive esophagitis, bleeding and lower esophageal stenosis may arise. Bradydiastalsis of the lower 2/3 of the esophagus causes dysphagia and odynophagia. Among the cases with Abnormal X-ray results, about 40% do not have any symptoms. Part of the patients may present with abdominal pain, abdominal distension and alternating diarrhea and constipation.

(2) Cardiovascular System

Cardiac involvement of various degree occurs in about 61% of the patients, which can be myocarditis, pericarditis and endocarditis. Clinical manifestations include dyspnea, chest distress, angina, arrhythmia, left or whole heart failure in severe cases (or right heart failure as a consequence of pulmonary heart disease caused by lung lesion), and even sudden cardiac death. Electrocardiographic abnormality is discovered in approximately 50% of the patients.

(3) Respiratory System

Abnormal chest imaging results are discovered in 40% of the patients, most of which are diffuse interstitial fibrosis of the lungs. Pulmonary dysfunction is also noticed, with a 70% decrease in vital capacity. Clinical manifestations include cough and progressive dyspnea.

(4) Urology System

75% of the patients are discovered to have kidney involvement, which can be sclerosing glomerulonephritis accompanied by proteinuria, hypertension, nitremia, and acute kidney injury in severe cases. Prognosis of individuals with kidney damage is often poor.

(5) Nervous and Mental System

A small number of patients suffer from polyneuritis (cranial nerves included), convulsions, seizure, personality change, cerebral arteriosclerosis or cerebral hemorrhage. Accesory examinations show protein elevation in cerebrospinal fluid and abnormality in electroencephalogram.

6. Others

(1) Calcium deposits occur in the skin above the finger and other joints and soft tissues in the extension sides of the limbs.

(2) CREST Syndrome

CRST syndrome is named according to calcinosis cutis, Raynaud’s phenomenon, sclerodactyly and telangiectasia. Cases of CRST syndrome that present with esophagus hypomotility are called CREST syndrome, which is a subtype of SSc, whose prognosis is good.