Pericardial involvement in systemic sclerosis

Objective-To determine the frequency and histological characteristics of pericardial involvement in systemic sclerosis. Method-Necropsy sections of pericardium from 44 patients with systemic sclerosis were studied, together with sections from 19 age/sex matched controls. Sections were stained with haematoxylin and eosin, acid toluidine blue, and elastic van Gieson. Mast cells were counted in 10 random high power fields and the degree of fibrosis was quantified using a Chalkley count. Results-Chronic pericarditis was seen in 31 (77.5%) of the systemic sclerosis cases, but in only one of the controls. The characteristic changes of uraemic pericarditis were not seen. The degree of fibrosis was greater in those with systemic sclerosis, though numbers of mast cells, thought to be important in fibrogenesis, were similar in both groups. Myocardial fibrosis was seen in 15 (37.5%) of systemic sclerosis cases but in none of the controls. Conclusion-The incidence of pericarditis and myocardial fibrosis is much greater than in controls. The results indicate that pericarditis is a primary disease (rather than secondary to uraemia).