What are the causes of both central and peripheral demyelination, including conditions affecting the central nervous system (CNS) and peripheral nervous system (PNS)?

From the Guidelines

Central and peripheral demyelination can be caused by various conditions, including autoimmune diseases, infections, and inflammatory disorders.

Causes of Central Demyelination

• Multiple sclerosis (MS): a chronic autoimmune disease that affects the central nervous system (CNS) 1
• Neuromyelitis optica (NMO): an autoimmune disease that primarily affects the optic nerve and spinal cord 1
• Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disorder: a rare autoimmune disease that affects the CNS 1
• Acute disseminated encephalomyelitis (ADEM): a rare inflammatory disease that affects the CNS 1
• Infections: such as sarcoidosis, Sjögren syndrome, and neurotuberculosis 1
• Malignancy: such as leptomeningeal metastases or neurolymphomatosis 1
• Vitamin deficiency: such as Wernicke encephalopathy (vitamin B1 deficiency) or subacute combined degeneration of the spinal cord (vitamin B12 deficiency) 1

Causes of Peripheral Demyelination

• Guillain-Barré syndrome (GBS): an autoimmune disease that affects the peripheral nervous system (PNS) 1
• Chronic inflammatory demyelinating polyneuropathy (CIDP): a chronic autoimmune disease that affects the PNS
• Infections: such as campylobacteriosis or mycoplasma pneumoniae 1
• Vaccinations: in rare cases, vaccinations can trigger GBS 1
• Surgery: in rare cases, surgery can trigger GBS 1
• Malignancy: such as paraneoplastic neurological disorders 1

Common Triggers of Demyelination

• Infections: such as campylobacteriosis, mycoplasma pneumoniae, or Zika virus 1
• Vaccinations: in rare cases, vaccinations can trigger demyelination 1
• Surgery: in rare cases, surgery can trigger demyelination 1
• Autoimmune disorders: such as rheumatoid arthritis or lupus 1

From the Research

Causes of Central and Peripheral Demyelination

The causes of central and peripheral demyelination can be attributed to various factors, including:

• Autoimmune disorders, where the immune system mistakenly attacks the myelin sheath in the central nervous system (CNS) and peripheral nervous system (PNS) 2, 3
• Inflammatory demyelinating diseases, such as multiple sclerosis (MS) and chronic inflammatory demyelinating polyradiculopathy (CIDP) 2, 4
• Genetic predisposition, which may contribute to the development of demyelinating diseases 5
• Environmental factors, such as infections and exposure to toxins, which may trigger demyelination in susceptible individuals 3, 6

Conditions Affecting the CNS and PNS

Several conditions can affect both the CNS and PNS, including:

• Combined central and peripheral demyelination (CCPD), a rare disease entity characterized by simultaneous or sequential demyelination in both the CNS and PNS 2, 3, 4, 6
• Multiple sclerosis (MS), a chronic inflammatory demyelinating disease that primarily affects the CNS, but can also involve the PNS 2, 3
• Chronic inflammatory demyelinating polyradiculopathy (CIDP), a peripheral demyelinating disease that can also affect the CNS 2, 4
• Guillain-Barré syndrome (GBS), an acute inflammatory demyelinating disease that primarily affects the PNS, but can also involve the CNS 3, 6

Mechanisms of Demyelination

The mechanisms of demyelination in CNS and PNS diseases are complex and multifactorial, involving:

• Autoimmunological reactivity against myelin antigens or epitopes present in both the CNS and PNS 3
• Higher general susceptibility to autoimmune disease, which may be caused or exacerbated by immunomodulatory treatment 3
• Coincidental co-occurrence of CNS and PNS demyelination 3