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Different pathological processes for acute white matter lesions in multiple sclerosis.
M Alturkustani1, B Bahakeem, Q Zhang
1King Abdulaziz University, Jeddah, Saudi Arabia. alturkustani.murad@gmail.com.
The Malaysian Journal of Pathology
|August 30, 2020
Summary
Acute lesions in multiple sclerosis (MS) show varied pathologies beyond demyelination, including axonal degeneration. This suggests diverse underlying mechanisms contributing to MS lesion development.
Area of Science:
- Neuropathology
- Neuroimmunology
- Demyelinating Diseases
Background:
- Multiple sclerosis (MS) presents with diverse clinical, prognostic, and pathological features.
- Understanding the precise nature of acute MS lesions is crucial for elucidating disease pathogenesis.
Purpose of the Study:
- To pathologically review acute MS lesions, focusing on axonal injury, myelin loss, and glial response.
- To differentiate between primary and secondary demyelination in MS lesions.
Main Methods:
- Retrospective analysis of 8 surgical acute lesion biopsies from patients with clinical MS diagnoses.
- Pathological examination of white matter lesions for myelin, axons, and cellular reactions.
Main Results:
- Three distinct pathological patterns were identified in acute MS lesions.
- Pattern 1 (typical plaques): nearly complete demyelination with axonal preservation/swelling.
- Pattern 2: mixed demyelination with preserved myelinated axons and axonal swelling.
- Pattern 3: reduced myelin staining with fragmented axons and apoptotic nuclei, suggesting axonal degeneration without clear demyelination.
Conclusions:
- Acute MS lesions exhibit pathologies beyond pure demyelination, including axonal degeneration.
- Lesions can involve primary demyelination alone or in combination with axonal damage.
- These findings indicate varied pathogenesis underlying acute MS lesions.
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