Early ultrastructural alterations in adult dermatomyositis. Capillary abnormalities precede other structural changes in muscle

M. de Visser, A. M. Emslie-Smith, A. G. Engel

Research output: Contribution to journalArticleAcademicpeer-review

102 Citations (Scopus)


In 6 adults with dermatomyositis, minimally weak or nonweak muscles that showed inconclusive light-microscopic alterations were examined by electron microscopy. In all 6 specimens, this revealed pathologic changes in endomysial capillaries. The endothelial cells harbored microtubular inclusions and microvacuoles in all cases; pale swollen endothelial cells were observed in 3 specimens. There were no significant ultrastructural changes in the muscle fibers. In all cases, a small proportion of muscle capillaries were immunoreactive for complement membrane attack complex neoantigens. The findings imply that in adult dermatomyositis capillary injury precedes muscle fiber damage and infiltration by inflammatory cells, and that the microvasculature is an early and specific target of the disease process in muscle
Original languageEnglish
Pages (from-to)181-192
JournalJournal of the neurological sciences
Issue number1-3
Publication statusPublished - 1989

Cite this