Histology Assignment about skeletal muscle diseases

1. Skeletal muscle diseases
Made by: Mahmoud Bassiony Abdallah

2. Definition
• Skeletal muscle diseases or myopathies are disorders
with structural changes or functional impairment of
muscles.
• Diagnosis of myopathies is based upon clinical
features of patients and investigations.

3. Classification
• Acquired myopathies
 Inflammatory myopathies
 Endocrine myopathies
 Toxic or drug-induced myopathies
• Hereditary myopathies
• Muscular dystrophies
• Congenital myopathies
• Metabolic myopathies
• Mitochondrial myopathies

4. Inflammatory myopathies
• Largest group of acquired and potentially treatable
causes of skeletal muscle weakness .
 Inclusion body myositis(IBM
 Polymyositis (PM)
 Dermatomyositis (DM)
 Non-specific myositis (NSM)
 Immune-mediated necrotizing myopathy (IMNM)

5. Cross section of normal skeletal muscle
Epimysium
perimysium

6. LM picture of PM,DM and IBM
Rimmed vacuoles

7. Muscular Dystrophies(MD)
• Group of inherited myopathies characterized by
progressive muscle weakness and wasting.
• Heart and other organs can also be affected.
• Subdivided on the basis of mode of inheritance, age
at onset, distribution, rate of progression and
prognosis.
• 9 major types

8. Classification of muscular dystrophies
• Sex-linked:
 Duchene muscular dystrophy
 Becker’s muscular dystrophy
 Emery-dreifuss muscular dystrophy
• Autosomal recessive:
 Limb girdle muscular dystrophy
 Fascioscapulohumeral dystrophy
• Autosomal dominant:
 Oculopharyngeal muscular dystrophy
• Myotonic dystrophy
• Distal myopathy
• Congenital muscular dystrophy

9. LM picture of DMD,BMD,EDMD,MMD and FSHD

10. THANK
YOU