Difference Between Axonal Neuropathy and Demyelinating Neuropathy (With Table)

Problems of the central nervous system can be disabling since they influence our movements and our sensory processes. Neuropathy is a scientific word that refers to any disorder that affects the neurons. Both these given neuropathies are nerve disorders. People may often mix them up with one another. However, they are not the same thing and have some points of difference between them.

Axonal Neuropathy vs Demyelinating Neuropathy

The main difference between Axonal Neuropathy and Demyelinating Neuropathy is that Axonal neuropathy is a neurological condition characterized by the loss and disintegration of axons, whilst Demyelinating neuropathy is characterized by the breakdown of the insulation called myelin (a fatty layer of an insulating substance that surrounds the axons of nerve cells). Any auto-immune disorder in which auto-antibodies assault the covering of motor neurons without generating swelling or myelin breakdown is the main reason for axonal injury. Demyelinating ailments, on the other hand, are commonly caused by hereditary factors, viral factors, and autoimmune responses.

Harm to a specific section of the peripheral nerves termed axons, which are the projections of neurons that carry nerve signals, causes axonal neuropathy. This reason is a defining aspect of this disorder. Sensory, motor, and autonomic fibers are all affected, and the condition is deadly. Axonal neuropathy can be managed with intravenous immunoglobulins or plasmapheresis. Treatment is primarily determined by the nature of the damage and the accompanying symptoms.

Demyelinating neuropathies have a wide range of clinical manifestations: They can have a hereditary or acquired origin, an acute or chronic time point, and a multicenter or widespread dispersion. They can have phenotypes ranging from an indolent illness that starts in childhood and develop gradually over time (as in a hereditary form) to neuropathy with a severe clinical onset and rapid advancement that leads to tetraparesis and respiratory arrest.

Comparison Table Between Axonal Neuropathy and Demyelinating Neuropathy

Parameters of Comparison

Axonal Neuropathy

Demyelinating Neuropathy

Definition

It is a neurological condition characterized by the loss and disintegration of axons.

Characterized by the breakdown of the insulation called myelin.

Cause

Any auto-immune disorder in which auto-antibodies assault the covering of motor neurons without generating swelling of myelin breakdown.

It happens due to hereditary factors, viral factors, and autoimmune responses.

Impulse Conduction Velocity

Hindrance of impulse transmission velocity at distal sites only.

Hindrance of impulse transmission velocity at both proximal and distal sites.

Loss of Reflexes

Sensitivity declines in muscles that aren’t exceptionally weak or wasteful.

In the context of wasting and frailty of the foot, there is a specific impairment of the ankle shock reflex.

General Point

It causes a paralytic feeling in the limbs.

Causes muscle weariness and weakness.

What is Axonal Neuropathy?

Axonal neuropathy is a neurological condition characterized by the loss and disintegration of axons.

Every auto-immune disorder in which auto-antibodies affect the covering of motor neurons without generating swelling or myelin breakdown is the major cause of axonal injury. The sensory nerves are usually unaffected, but the motor nerves are. Motor nerves are responsible for transmitting signals from the brain to the body, such as reflexes. Axonal neuropathy is present in a type of Guillain Barre Syndrome in the diagnosis of severe illnesses. It is present in persistent disorders such as diabetes, leprosy, and other diseases when both motor and sensory nerves are affected as the disease advances.

Muscular motions are altered medically in axonal neuropathy. Tingling, stiffness, and a quivering feeling have been reported. Temperature sensibility may be lost in the affected region. There is sensory impairment but no loss of reflexes. Axonal neuropathy causes a paralytic sensation in the appendages.

Axonal injury is more likely to cause partial impairment of the ankle shock sensation in the context of wasting and weakening of the foot.

The impulse conduction velocity reported from distal muscles like the foot and ankle is lower in patients with axonal neuropathies, although it is reasonably normal for intermediate regions like the forearms.

What is Demyelinating Neuropathy?

Demyelinating neuropathy is characterized by the breakdown of the insulation called myelin (a fatty layer of an insulating substance that surrounds the axons of nerve cells).  

Genetic origins, infectious agents, and immunological responses are the most major culprits of demyelinating diseases. Antibodies progressively damage the myelin that covers the axons of neurons in these. Because this myelin layer is required for quicker signal transduction, impulse communication is either exceedingly slow or lost once myelin is eliminated. This condition damages sensory neurons. Not only that but also, motor neurons can suffer damage due to this neuropathy.

It has been proven that if demyelinating disorders are not managed promptly, the axons will be damaged as well.

Muscle weakness and weariness are common symptoms of demyelinating neuropathy. There is also fuzzy vision, split vision, mobility difficulties, and muscular loss of coordination. Moving and balancing become problematic in terms. Urinary and fecal incontinence are both present. A common symptom of demyelination is the loss of responses in muscles that aren’t especially weak or wasted.

This condition results in the hindrance of impulse transmission velocity at both proximal and distal sites.

Demyelinating neuropathies can have phenotypes ranging from an indolent illness that starts in childhood and develop gradually over time (as in a hereditary form) to neuropathy with a severe clinical onset and rapid advancement that leads to tetraparesis and respiratory arrest.

Main Differences Between Axonal Neuropathy and Demyelinating Neuropathy

  1. Axonal Neuropathy is a neurological condition characterized by the loss and disintegration of axons, while Demyelinated neuropathy is characterized by the breakdown of the insulation called myelin. 
  2. Axonal neuropathy is caused by an auto-immune disorder in which auto-antibodies assault the covering of motor neurons without generating swelling of myelin breakdown. On the other hand, Demyelinated neuropathy is caused by hereditary factors, viral factors, and autoimmune responses.
  3. Hindrance of impulse transmission velocity at distal sites only occurs in axonal neuropathy, whereas hindrance of impulse transmission velocity at both proximal and distal sites occurs in Demyelinated neuropathy. 
  4. Axonal Neuropathy causes sensitivity declines in muscles that aren’t exceptionally weak or wasteful. In Demyelinated neuropathy, in the context of wasting and frailty of the foot, there is a specific impairment of the ankle shock reflex.
  5. Axonal neuropathy causes a paralytic feeling in limbs, unlike Demyelinated neuropathy that Causes muscle tiredness and weakness.

Conclusion

Therefore, we can see that both these neuropathies are closely related and are quite similar to each other. The fundamental distinction is in the state of sensory nerves, which transmit experiences from the receptors to the brain.

Treatment for these disorders entails a change in lifestyle, a reduction in alcohol consumption, and the avoidance of brain harm. Although autoimmune activities cannot be prevented, the inciting causes can be managed, and the damages managed. Axonal neuropathy can be managed with injectable immunoglobulins or plasmapheresis. Treatment is primarily determined by the nature of the injury and the accompanying symptoms. Steroids are widely used in the treatment of both neuropathies.

References

  1. https://jamanetwork.com/journals/jamaneurology/article-abstract/781940
  2. https://jnnp.bmj.com/content/63/2/163.short