Marfan's disease and Erdheim's cystic medionecrosis. A study of their pathology.

Differentiation between Marfan's disease, or its forme fruste counterpart and Erdheim's cystic medionecrosis can be made in cases of aortic dilatation or dissection. This study examined the morphological features at light microscopy of aortic tissue, removed at surgery in 10 patients with Marfan's disease. A separate group consisted of 24 patients who did not express the complete Marfan phenotype but had family members who displayed the full and typical features of the disease. This group represented the so-called 'forme fruste' variant. These two groups were compared with 12 patients in whom a histopathological diagnosis of Erdheim's cystic medionecrosis had been made. Finally normal aortic tissue from post-mortem subjects were made available representing controls. In each case the degree of elastic fragmentation and cystic change of the aortic media was assessed and tabulated. The results indicate that severe fragmentation of elastic is similarly identifiable in both Marfan and Marfan forme fruste groups and that differentiation is easy pathologically from subjects with the comparatively modest fragmentation seen in Erdheim's cystic medionecrosis. Although cystic change was encountered in all groups, its severity tended to parallel the age of the subject, and we consider from our study that Erdheim's cystic medionecrosis represents no more than an exaggerated age-related change.