Scleroderma (systemic sclerosis) is a disease of unknown etiology and is of worldwide distribution. Women are affected more as compared to men (3: 1) and are usually seen after the age of 30 years. Its onset in childhood is unusual.
It is characterized by thickening and fibrosis of the skin, obliterative lesions of the arterioles and capillaries along with involvement of the various visceral organs.
Although the involvement of skin is the usual presentation in most of the cases yet it is the visceral involvement of various organs like heart, kidneys, lungs and gastrointestinal tract which produces morbidity of the disease.
Scleroderma can manifest in various forms:
1. Circumscribed Scleroderma (Morphoea). It is a localized form of the disease which occurs in the form of plaques (Single or multiple), round oral or irregular, pale or skin coloured, smooth wax like. These patches may become confluent and spread to wide areas of skin. However the face usually is not involved.
Another form is linear scleroderma when sclerotic and pigmentary changes occur in a linear fashion on the limbs and face. This gives rise to typical “mouse head” appearance.
2. CREST syndrome. It is a limited form of cutaneous scleroderma where there is symmetrical thickening of skin confined to fingers, extremities and the face. When this form manifests with calcinosis, Raynaud’s phenomenon, oesophageal dysmotility, Sclerodactyly and telangiectasia, it is labeled as CREST SYNDROME. It is a relatively benign condition but some patients may develop severe form of pulmonary hypertension.
3. Systemic sclerosis. This is a progressive from of disease which affects various internal organs like kidney, Heart, lungs, gastrointestinal tract and musculo skeletal system in addition to rapid symmetrical thickening of skin in various parts of body.
Scleroderma is a disease of undetermined artiology. Abnormalities of both humoral and cellular immunity have been observed. Early skin lesions show T lymphocytes infiltration of the dermis before fibrosis occurs and in some patients there is T-ceil sensitization to collagen indicating thereby that delayed hypersensitivity to collagen might initiate a circle of lymphokine release with resultant more production of collagen.
Abnormalities of T-cell population include decreased CD 8 suppressor cell activity and increased CD-4 helper cell activity. Natural killer cell (NK) a sub population of lymphocytes activity is also reduced. These cells participate in the control of immune system.
Nonspecific serologic abnormalities (hypergammaglolulinemia, positive speckled or nucleolar antinuclear antibodies and rheumatoid factor) presence in cases of 5.5. is a pointer to the role of disordered humoral immunity.
Environmental factors like exposure to silica dust (coal and gold miners) Vinyl chloride, Aromatic hydrocarbons (Benzine, Toluene) and use of adultered cooking oil are known to be responsible for producing the disease.
Use of drugs like Pentazocine and Bleomycin (an anticancer agent) has also resulted in production of fibrosis, pigmentation of skin and pulmonary fibrosis. Familial incidence of the disease has been seen. 5.5. occurs with greater frequency in patients with HLA – DR1, DR2, DR3, DRW5, DRW52 and HLA-B8.
Pathology of Scleroderma
The characteristic change is the over growth of collagen and fibroblasts with thickening of dennal capillaries and arterioles. There may be dermal edema with lymphocytic infiltration. As disease progresses, there is increase in dermal collagen and epidermal atrophy. Arteriolar lumen gets obliterated by intimal proliferation and subsequently due to fibrosis and atrophy, blood supply to various viscera suffers.
In gastrointestinal tract there is progressive atrophy of the esophageal wall involving mainly the sub mucosa and muscalris. These changes are present in the rest of G.I. tract though the degree of fibrosis is less than the skin.
Non-specific inflammatory synovitis resembling that of rheumatoid disease may appear at early stage. Muscles show lesions resembling myopathy. There is fragmentation, loss of striation of muscle fibres and focal inflammatory infiltrates, In many cases, the involved muscles are replaced by fibrosis.
Kidneys are involved in more than 60% of cases. There is intimal hyperplasia, fibrinoid necrosis of the afferent arterioles and glomerular tufts as well thickening of glomerular basement membrane. Micro infarcts appear in the cortex and glomeruloscierosis leading to malignant hypertension develops.
Lungs develop diffuse interstitial fibrosis with progressive thickening of small pulmonary vessels. Because of pulmonary fibrosis chronic cor pulmonale may develop.
Heart shows focal interstitial fibrosis and degeneration of myocardial fibers. Involvement of conduction tissue leads to various forms of cardiac arrhythmias. Pericarditis may develop in some. Involvement of small arteries and arterioles leads to their narrowing and when it occurs in small vessels of the fingers, picture like Raynauds Phenomenon may appear.
Clinical picture of Scleroderma
Systemic sclerosis (Scleroderma) begins insidiously. All cases exhibit skin changes in the form of thickening confined initially to small fingers. There is edema, induration and swelling of the hands which extends upwards.
This phase may last for a few weeks to months and gradually skin becomes firm and thickened. Tightening of the skin leads to loss of its pliability. Face is invariably involved leading to loss of wrinkles and furrows on face. It assumes a typical ‘mouse head’ appearance characterized by beaked nose, mask like face beaked nose and microstomia.
Raynaud’s phenomenon can precede skin changes by several months. It is characterized by involvement of small digital blood vessels leading to vaso spasm. Pigmentary changes in the form of hyper pigmentation and hypo pigmentation develop (salt and pepper skin).
Because of the stiffness and involvement of joints due to tautness of sclerotic skin, movements of the joints become restricted. A form of leathery crepitus may be felt during movements of affected joints.
In patients with limited cutaneous form of disease, calcific deposits develop in intracutaneous and subcutaneous tissues. Ulceration may appear in fingertips and over bony prominence. This is likely to become secondarily infected.
Esophageal involvement leads to fullness in epigastric region. Peptic oesophagitis may develop. Difficultly in swallowing of solid foods is invariably present. Involvement of small intestines leads to hypomotiity and malabsorption like picture.
Interstitial fibrosis of lungs leads to restrictive form of disease with impaired diffusing capacity. Lungs may show not only fibrosis but also honey combing and cyst formation. Pulmonary hypertension develops in patients of long standing. This often leads to picture of chronic cor pulmonale.
Cardiac involvement is in the form of pericarditis, diffuse myocardial fibrosis and various forms of arrhythmias. Renal involvement results in malignant hypertension and progressive renal failure. It is a serious complication of systemic sclerosis and carries high degree of mortality.
Eyes may show dryness and picture of sjogrens syndrome. Neurological involvement may be in the form of various neuropathies (Trigeminal neuralgia,carpal tunnel syndrome) Hypothyroidism may be seen in large number of patients and is associated with raised levels of anti-thyroid antibodies. Male patients of scleroderma are known to develop impotence.
Anemia of chronic infection (normocytic normochronic anaemia) is generally present. Erythrocyte sedimentation rate (ESR) is elevated. Hypergammaglobulinaemia with elevation of IgG is present. Rheumatoid factor though in low liters is found in 20-25% of patients.
Antinuclear antibodies are present in more than 90% of cases. Antinucleolar antibodies which are specific for systemic sclerosis are present in 20-30% of patients.
Barium study of esophagus will show a narrowed esophagus (screw type) while X-rays of hands may show subcutaneous calcinosis. In advanced cases there is erosion of the tufts of the distal phalanges. X-ray chest will reveal honey combing and fibrosis in the lower thirds of the lungs.
For Scleroderma, it is mainly supportive. Patient is advised to protect himself/herself from exposure to sunlight and extremes of climate. Dryness of skin may be reduced by avoiding use of detergents, soaps and applying regularly oil.
Regular exercises may help to maintain flexibility of joints. Massage may be also of help. Non steroidal anti-inflammatory drugs (NSAIDs) may give relief from myalgia and joint pains.
D-penicillamine is the drug of choice for reducing skin thickening and development of visceral involvement. It also leads to diminution of collagen production by its immuno suppressive action. Dose initially is 250 mg per day and can be increased to 1.5G/day after 1-3 months.
Best results are obtained by giving the drug 1 hour before or 2 hours after meals. Side effects include aplastic anemia, leukopenia, thrombocytopenia, glomerulonephritis, fever, rash, anorexia and myasthenia gravis.
Azathioprine is given in patients with progressive disease. Role of corticosteroids is controversial. These are mainly indicated in cases with pericarditis and inflammatory myositis. Renal lesions maybe aggravated by their use.
Raynaud’s phenomenon is helped by the use of dipyradimole, nifedipine verapamil, diltiazim and prazosin. Beta blocking drugs may make Raynaud’s phenomenon worse. In some case cervical sympathetomy helps though it gives only temporary improvement. Hypertension due to renal involvement is managed by the use of ACE inhibitors such as captopril and enlarpil.
Reflex oesophagitis is treated with small frequent feeds, antacids and use of drugs like Ranitidine. Renal failure may require dialysis. In the presence of hypertension, anti hypertension drugs are effective.
In addition to medical treatment, patient should be advised to lead a stress free life. Skin ulcers should be treated by local suigical dressing. Nitroglycerine paste applied to the ulcer may help in its healing.
Course and prognosis
Cases of systemic scleroderma when there is wide spread involvement of various viscera carry poor prognosis. Those with limited cutaneous disease have good prognosis, while those with rapidly progressive disease like renal involvement, pulmonary fibrosis, pericarditis and cardiac arrhythmias carry unfavorable prognosis.