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[Ultrastructural changes in skeletal muscle in polymyalgia rheumatica].
Deutsche Medizinische Wochenschrift (1946)
|November 21, 1986
Summary
Electron microscopy revealed characteristic ultrastructural changes in skeletal muscle mitochondria of polymyalgia rheumatica (PMR) patients. These findings suggest a systemic process affecting both muscle and arteries in PMR and giant cell arteritis.
Area of Science:
- Rheumatology
- Pathology
- Cell Biology
Context:
- Polymyalgia rheumatica (PMR) is a common inflammatory condition affecting older adults.
- Understanding the underlying pathophysiology of PMR is crucial for effective management.
- Previous studies have focused on arterial involvement, but skeletal muscle changes require further investigation.
Purpose:
- To investigate the ultrastructural changes in skeletal muscle of patients with polymyalgia rheumatica (PMR).
- To identify characteristic ultrastructural patterns in PMR skeletal muscle.
- To compare skeletal muscle changes with those in muscular arteries to elucidate a potential common systemic process.
Summary:
- Electron microscopy of skeletal muscle from 21 PMR patients revealed regressive, nonspecific focal changes.
- A characteristic ultrastructural pattern emerged when assessing 15 criteria, with significant mitochondrial alterations due to crystal deposition and deformation.
- These mitochondrial changes impair cell respiration but are compensated by increased mitochondria formation, indicating a distinct cellular response in PMR.
Impact:
- The study identifies specific ultrastructural muscle changes in PMR, offering a potential diagnostic profile.
- Analogous morphological changes in skeletal muscle and muscular arteries suggest a shared systemic harmful process in PMR and giant cell arteritis.
- These findings challenge explanations based solely on arterial occlusions and highlight the systemic nature of PMR.
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