-IBIS-1.5.0-
tx
immune system
scleroderma
diagnoses

definition and etiology

definition: A chronic disease of unknown etiology characterized by inflammatory, vascular, and fibrotic changes of the skin, internal organs (esp. GI tract, esophagus, thyroid, kidney, heart, lungs, and heart), and articular structures. It is also called Progressive Systemic Sclerosis (PSS).

etiology: The skin thickening and restriction follows an idiopathic overproduction of collagen. The disease is highly individual in terms of severity and progression. Some patients may experience only skin changes and restrictions in the hands and face for decades before visceral or organ involvement begins. Others may rapidly develop generalized cutaneous thickening and often lethal internal organ disease. The full manifestation of the disease is known as the CREST Syndrome: Calcinosis, Raynaud's phenomenon, Esophageal dysfunction, Sclerodactylia, and Telangiectasia.

Scleroderma is seen in women four times as often as in men, and is rare in children. It is found worldwide but more rarely in Asia. The usual age of onset is around 20-40.

signs and symptoms

typical initial complaints include:
• Raynaud's phenomenon.
• Skin thickening of the fingers.
• Swelling of the extremities.

as the disease progresses:
• Skin becomes hyperpigmented.
• Skin of the whole upper body may become firm, leathery: the face looks masklike. The lower extremities are not usually affected much.
• Flexion contractures of the fingers, wrists, elbows.
• Subcutaneous calcifications or ulcers develop on the bony prominences.
• Telangiectasias.
• Skin becomes dry and rough and loses hair and the ability to sweat.
• Restricted opening of the mouth.
• Esophageal dysfunction: the esophagus is the most commonly involved visceral organ: dysphagia, regurgitation of stomach contents, and peptic esophagitis often occur.
• Joint pain/swelling/stiffness of fingers and knees.
• Small intestine involvement: Malabsorption, steatorrhea, weight loss, bloating, abdominal pain.
• Large intestine involvement: chronic constipation and fecal impaction.
• Respiratory/cardiovascular involvement: fibrosis of the lungs causes exertional dyspnea, dry cough, pleurisy; cardiac problems: causing 15% of PSS deaths: include arrhythmias, pericarditis, and conduction disturbances.
• Renal involvement: causes half the deaths of PSS: acute failure causes rapid development of severe (possibly malignant) hypertension.

lab findings: reflect specific organ involvement
• Elevated ESR in two-thirds of cases.
• Possible anemia: Malabsorption may predispose to vitamin B12 or folate acid anemia.
• Elevated levels of IgG.
• (+) RF is found in 25% of PSS patients (Harrison's) or absent (Merck).
• ANA is found in 33-96% of patients (Harrison's), 60% (Wallach), or is absent (Merck).
• Biopsy of affected skin and deep fascia is diagnostic.
• Mild hypochromic microcytic anemia may be present.

course and prognosis

Although the course of the disease is variable and unpredictable, it is characterized by a slowly progressing involvement of the skin and/or visceral organs. Remissions are rare but do occur. The disease is typically very gradual: 80% of patients will be alive after 2 years and 20% will be alive after 10 years. The disease is most severe in black women; in whites, men are often affected worse than women. The usual causes of death are renal, cardiac and/or lung complications.

differential diagnosis

• Rheumatoid Arthritis.
• SLE.
• Polymyositis.
• Scleredema.
• Scleromyxedema.
• Primary amyloidosis.
• Raynaud's is also seen in: thoracic outlet syndrome, trauma (e.g. use of a jackhammer), previous cold injury, and vinyl chloride exposure.


footnotes