Progressive Systemic Sclerosis (PSS): Slceroderma, Its Clinical Relevance, Diagnosis And Presentations
A General Overview
In this generalized disorder of connective tissue, fibrosis and degenerative changes predominate. The skin, synovium, digital arteries, gastrointestinal tract, lungs, heart, Kidney and other organs may be affected. The most conspicuous feature is thickening and hardening of the skin which becomes “hide-bound”. Depending on the extent and clinical presentation, the following entities have been recognized.
- Localised slceroder,a (morphoea): The lesion is restricted to a localized area of the skin.
- Linear scleroderma: The skin involvement is linear. It leads to atrophy of underlying tissues. In the face it gives a characteristic appearance.
- Disseminated morphoea: There are multiple skin lesions, but systemic involvement is minimal or absent.
- CREST syndrome: This consists of calcification of subcutaneous tissues, Raynaud’s phenomenon, esophageal hypomotility, sclerodactyly and telangiectasia.
- Progressive systemic sclerosis: There is progressive involvement of skin and other internal organs leading to systemic manifestations. This carries the worst prognosis.
Slceroderma occurs all over the world and is occasionally seen in Indian subjects.
Pathology: The prominent pathological abnormality is overproduction and cross linking of collagen and vasculitis.
Skin: The dermal collagen is increased leading to fibrosis. Endarteritis and calcinosis supervene in some cases.
Joints: Synovium shows infiltration with lymphocytes and plasma cells and deposition of fibrin. The changes may resemble those of rheumatoid disease, but pannus formation is unusual.
Kidney: Changes occur in the interlobular arteries. These comprise intimal hyperplasia, fibrinoid necrosis of afferent arterioles and glomerular tufts, and thickening of glomerular basement membrane. These changes lead to cortical infarctions and glomerulosclerosis. The lesions may resemble those seen in malignant hypertension.
Muscles: The histological lesions resemble those seen in myopathy such as fragmentation and loss of striation of muscle fibers and nuclear changes. Affected muscles are replaced by fibrosis.
Vasculitis: Affection of small arteries leads to intimal thickening and narrowing of lumen. The lesions are particularly demonstrable in the digital arteries of patients showing Raynaud’s phenomenon.
Physical Presentation In Scleroderma
The disease is seen in the fifth and sixth decades and females predominate. Onset is insidious. The initial symptoms are variable. These include Raynaud’s phenomenon, tightness of the extremities, arthralgia and vague manifestations.
Cutaneous manifestations: Three stages can be distinguished during the evolution of the disease. There are dermatous, indurative and atrophic stages. Initial manifestations are edema of the hands and feet, which may extend more proximally. The edema is followed by thickening and tightening of the skin. Skin loses its normal pliability and ultimately becomes “hidebound” and non-plachable. Appendages are lost over the affected areas. Affection of the face gives rise to the “mouse head” appearance with microstomia, beahed nose, mask like expression and difficulty in opening the mouth.
Pigmentary changes develop over the extremities and anterior chest wall. These consist of hyperpigmentation or a combination of spotty hyper and hypopigmentation (“salt and pepper skin”), and telangiectasia over the fingers, palms, face, lips and tongue. The tight atrophic skin is particularly vulnerable to trauma. Painful, non-healing, chronic, indolent ulcers are common over the fingers and toe tips. When the extremities are predominantly affected, the condition is called acrosclerosis. Over the palmar aspect of the terminal phalanges, subcutaneous calcification occurs. These ulcerate and extrude calcareous material. Ischemia aggravates this tendency. Paroxysmal vasopasms of digital blood vessels leads to Raynaud’s phenomenon, which is present in 95% of cases, when exposed to cold environment. Raynaud’s phenomenon may also occur during emotional disturbances or even spontaneously.
© 2014 Funom Theophilus Makama