Axonal particles with electron-dense cores from arterial biopsy in polymyalgia arteritis

Electron microscopic examination of nerve tissue from a patient with polymyalgia arteritis has shown the presence of electron-dense particles within the axons. These particles have a viral-like structure but lie within the size range of small neurosecretory vesicles and may represent alterations in these organelles. Myelin-like bodies have also been identified within non-myelinated axons and are suggestive of lysosomal end-products. These findings seem to bear out the proposition that the primary lesion in polymyalgia arteritis may be neurogenic in origin and offer some explanation of the pain experienced in the course of the disease.