Demyelinating processes, or diseases, are conditions characterized by damage to the myelin sheath, the protective sheath that covers nerves within the central nervous system, according to MayoClinic.com. As the myelin sheath becomes damaged, patients will experience a variety of neurological deficits. Demyelinating diseases include multiple sclerosis, transverse myelitis, optic neuritis and many other conditions. Each demyelinating disease has a variety of symptoms that point to damage of the myelin sheath.
Limb Weakness
One of the cardinal symptoms of transverse myelitis, a common demyelinating disease, is weakness in the patient's arms and legs, reports the National Institute of Neurological Disorders and Stroke. The weakness begins in the lower part of the legs. As the destruction of the myelin sheath progresses, weakness will spread to the thigh and arms. This weakness can cause dragging of the feet and uncoordinated movements. In more severe cases, the patient will experience paralysis of the limbs.
Muscle Spasms or Tremors
Multiple sclerosis, a demyelinating disease process, can present with episodes of muscle tremors and spasms, notes MedlinePlus, a service of the National Institutes of Health. The disease causes inflammation and damage to the nerves that control the movements of the muscles. This damage prompts the muscles to move suddenly and erratically. Spasms can be painful. These muscular abnormalities worsen over time.
Blindness
The optic nerve, the nerve responsible for relaying sight to the brain, is the only cranial nerve affected by demyelinating diseases. Demyelination of the optic nerve can lead to partial blindness, reports the Merck Manuals Online Medical Library. As the myelin is stripped from the optic nerve, the visual pathway is slowed and disrupted. The nerve will be unable to transmit images to the brain and as a result, patients will experience gradual, progressive blindness in the affected eye.
Seizures
When large areas of the brain are stripped of myelin, which can occur in diseases such as acute disseminated encephalomyelitis, patients can develop seizures, according to MayoClinic.com. Demyelination causes damage to the parts of the brain that prevent seizures from occurring. When there are multiple demyelinated areas within the brain, patients experience seizures with increasing frequency.
Paresthesia
Paresthesia is the sensation of tingling, numbness or discomfort in an area of the body. Often this symptom is described as a pins and needles sensation. A demyelinating process can cause this symptom, states MedlinePlus. As the nerves in the central nervous system become demyelinated, they transmit abnormal messages to the brain which interprets these signals as paresthesia.
