A review of recent observations and current theories on the etiology and pathogenesis of progressive systemic sclerosis (diffuse scleroderma)

The immunopathology of progressive systemic sclerosis (PSS)

Progressive systemic (sclerosis) is one of the most enigmatic of the rheumatic diseases. It is a connective tissue disorder of unknown etiology characterized by fibrosis in skin and internal organs. Although similar lesions are found with increased prevalence in workers exposed to coal, gold, silica, and polyvinyl chloride, most patients have had no known predisposing factors. Select reports of a familial occurrence of PSS have been observed but a definitive genetic basis is lacking and no clear associations with the major histocompatability complex have been demonstrated. Moreover, although a variety of immunologic abnormalities in patients with PSS have been reported, they are generally diffuse and non-diagnostic. Such abnormalities include defects in cell mediated immunity, increases in sera immunoglobulins, antinuclear antibodies, and cryoglobulins. In contrast to these non-specific findings, there appears to be significant evidence of a relationship between cell mediated immunity to collagen and appearance of scleroderma. For example, peripheral blood lymphocytes in patients with scleroderma undergo lymphocyte transformation when cultured with specific collagen preparations. The pathology of skin and internal organs in PSS generally reflects both collagen deposition and small vessel occlusion. All organ systems may be involved but mortality significantly increases with involvement of heart, kidney, or lung. Unfortunately, at present a reliable experimental model of PSS has not been found although similar immunopathology can be induced in homologous disease of rats and in chronic graft vs host disease of humans.

Three siblings with scleroderma (systemic sclerosis) and two with Raynaud's phenomenon from a single kindred

A kindred is reported which contains 3 siblings with scleroderma, 2 siblings with Raynaud's phenomenon, and 2 first-degree relatives with histories suggestive of connective tissue syndromes. Studies of microvascular morphology and flow, serum endothelial cytotoxic activity, antinuclear antibodies, and HLA haplotypes in 18 relatives and 6 spouses revealed that 4 of 5 affected siblings expressed the HLA-DRw4 antigen, which was also present in 2 of 3 asymptomatic relatives whose serum contained endothelial cytotoxic activity. The evidence for an inherited susceptibility to scleroderma is reviewed.

Scleroderma in the elderly

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Progressive systemic sclerosis in the elderly

There is evidence to suggest that the incidence of progressive systemic sclerosis in the elderly is more common than in younger age groups. As in younger patients, late onset cases may have minimal skin changes and this can cause difficulty in diagnosis. The case histories of 2 patients are presented to illustrate these points.

Involvement of the eye in SLE and scleroderma. A study using fluorescein angiography in addition to clinical ophthalmic assessment

General examination of the eye was carried out in 22 patients with systemic lupus erythematosus (SLE) and in 10 with scleroderma. 3 of the SLE and 2 of the scleroderma patients had keratoconjunctivitis sicca. Fluorescein angiography showed abnormalities of the retinal vasculature in one of a subgroup of 12 SLE patients and one of 10 scleroderma patients. None of the 12 SLE patients had abnormalities of the choroidal vasculature, while 5 of the 10 scleroderma patients had patchy areas of nonperfusion of the choroidal capillary bed.

Progressive systemic sclerosis and autoimmune haemolytic anaemia

The development of progressive systemic sclerosis (PSS) in a patient with established autoimmune haemolytic anaemia is described. Points favouring an immunological aetiology for PSS are reviewed and discussed.

The Raynaud syndrome

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