Picornavirus-like crystals in subacute polymyositis.
01 Mar 1970-Neurology (Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology)-Vol. 20, Iss: 3, pp 205-205
TL;DR: The present report describes the electron-microscopic findings of numerous intracytoplasmic crystalline arrays resembling those of the picornavirus group in muscle of 2 patients who died after a subacute clinical course of dermatomvositis.
Abstract: RECENT STUDIES suggest that viruses may play a role in the etiology of poIymyositis-dermatomyositis. Myxovirus-like structures have been demonstrated in both sarcolemmal nuclei and sarcoplasm of muscle biopsy specimens obtained from a patient with chronic polymyositis.lV2 These structures were observed in 3 specimens taken during an eighteen-month period, suggesting that a chronic virus infection was involved in the pathogenesis of chronic polymyositis. Two other patients with clinicopathological diagnosis of chronic polymyositis demonstrated similar findings.3,4 The complexity and variability of the clinical pictures described in cases of polymyositis does not, however, permit the generalization that the disease might be related to a single etiologic agent. Because many different neurotropic viruses are known to cause muscle infections in mice,6 it seems reasonable to assume that different viral agents may play a pathogenic role in different types of human polymyositis. The present report describes the electron-microscopic findings of numerous intracytoplasmic crystalline arrays resembling those of the picornavirus group in muscle of 2 patients who died after a subacute clinical course of dermatomvositis. CASE REPORTS
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TL;DR: (First of Two Parts)
Abstract: Laboratory Features Elevation of sarcoplasmic enzymes in serum (creatine phosphokinase, aldolase, transaminases and lactic dehydrogenase) is valuable both for diagnosis and for following the clinic...
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TL;DR: IgG antibodies to human T-cell lymphotropic virus (HTLV-1) were found in 11 of 13 (85%) Jamaican patients with idiopathic adult polymyositis, and a striking association was first observed in 7 patients with poly myositis.
329 citations
TL;DR: The clinical picture is described, stressing the need for biopsy to ensure correct diagnosis of the treatment-resistant variant, inclusion body myositis, and several newer therapies under study for such cases are described.
Abstract: Idiopathic inflammatory myopathy, a category encompassing polymyositis, dermatomyositis, and a number of other disorders, is very uncommon, but has been the focus of intense study in the Arthritis and Rheumatism Branch of the National Institute of Arthritis and Musculoskeletal and Skin Diseases for the past several years. We describe the clinical picture, stressing the need for biopsy to ensure correct diagnosis. It is especially important to recognize the treatment-resistant variant, inclusion body myositis. The extraskeletal manifestations, particularly the cardiopulmonary, oropharyngeal, gastrointestinal, and endocrine involvement, are described. The cardiopulmonary involvement, especially interstitial lung disease, arrhythmias, and cardiac failure, may dominate the clinical picture. The known causes are varied, and include drugs, toxins, and some infectious agents, however, in most cases a cause cannot yet be identified. Circumstantial evidence suggests that picornaviruses may initiate some cases in humans, and a very similar disease in mice caused by a picornavirus is actively under study. Studies of autoantibodies and cellular immune function support a central role for disordered immunity in the pathogenesis. The myositis-specific autoantibodies, especially those directed at certain enzymes important in protein synthesis (the aminoacyl-transfer RNA synthetases), are found in a clinically distinct subset of patients. Although most patients respond initially to corticosteroids, cytotoxic drugs are sometimes added when steroid toxicity or refractoriness develops. We describe several newer therapies under study for such cases and outline future directions in research.
289 citations
TL;DR: Inclusion body myositis is a distinct but infrequently recognized inflammatory disease of skeletal muscle that lacks features of collagen-vascular disease, has a relatively benign and protracted course, frequently involves distal muscles, is found mainly in males, and does not improve with corticosteroid treatment.
Abstract: We report six cases of inclusion body myositis (IBM), a distinct but infrequently recognized inflammatory disease of skeletal muscle. Clinically, IBM differs from dermatomyositis and polymyositis. It lacks features of collagen-vascular disease, has a relatively benign and protracted course, frequently involves distal muscles, is found mainly in males, and does not improve with corticosteroid treatment. Electronmicroscopic demonstration of abnormal filaments in muscle cells is necessary for definite diagnosis, but IBM may be suspected by the finding on cryostat sections of numerous hematoxylinophilic granules in "lined" vacuoles in muscle cells. These correspond to whorls of cytomembranes. Although in dermatomyositis the capillary network is partly destroyed, in IBM it is usually augmented. A viral etiology of IBM has been suggested but remains unproven.
284 citations
References
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TL;DR: A technique for staining sections of osmium-fixed, epoxy-embedded tissues for light microscopy using aqueous toluidine blue at pH 11.1 and does not require prior removal of embedding medium, which permits better utilization of the full resolving power of the light microscope.
800 citations
TL;DR: Intranuclear and intracytoplasmic aggregates of filaments with tubular structures and transverse striations occurred in muscle tissues biopsied from a patient with chronic polymyositis, providing presumptive evidence that a chronic persistent viral infection may be involved in the pathogenesis of chronic polyMYositis.
Abstract: Intranuclear and intracytoplasmic aggregates of filaments with tubular structures and transverse striations occurred in muscle tissues biopsied from a patient with chronic polymyositis. The filamentous tubules bear a close resemblance to the incomplete form of myxovirus in which the envelope is missing. Three biopsies from the same patient, taken during a period of 1(1/2) years, all revealed these structures. This finding provides presumptive evidence that a chronic persistent viral infection may be involved in the pathogenesis of chronic polymyositis.
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