Guide To The Types Of Myelitis

Myelitis is a state of inflammation in an individual's spinal cord that can result in permanent nerve and spinal damage. Causes include damage from other diseases, abnormal autoimmune responses, certain types of viruses and bacteria, vascular abnormalities, and cancer. Symptoms vary depending on which section of the spinal cord is being affected and damaged from the inflammation. Examples include back pain, numbness, tingling, urinary urgency, bowel or bladder incontinence, abdominal tightness, muscle weakness, paralysis, loss of light touch sensation, and constipation. Myelitis is diagnosed with blood tests, diagnostic MRI imaging, physical exam, and lumbar puncture.

Myelitis treatment is essential. Common options include corticosteroids for transverse myelitis. Other medications for myelitis may be helpful. Patients often need occupational therapy or physical therapy for myelitis as well. However, the best treatment for myelitis varies depending on the specific type. Thus, patients must understand the major types of myelitis first.

Transverse Myelitis

Transverse myelitis is a type where the patient experiences nerve dysfunction on both sides of their spinal cord in both the sensory and motor pathways. There are a handful of classic symptoms that occur in individuals with this condition. Symptoms include arm and leg weakness, tingling sensations, discomfort or pain, numbness, bladder dysfunction, and bowel motility issues. These symptoms may occur bilaterally, which means they appear in both arms and legs. However, they may also occur unilaterally, meaning in the arm and leg on one side of the body.

The word transverse in the name of this condition refers to malfunction at a single level across the entire spinal cord. Inflammation that is focal and produces unilateral dysfunction is included in this myelitis classification. Most cases of transverse myelitis have an unknown cause. The ones that do are often the result of an autoimmune disorder. Examples include neuromyelitis optica, Sjogren's syndrome, andmultiple sclerosis.

Leukomyelitis

Leukomyelitis describes inflammation of the spinal cord limited to an individual's white matter. The brain and spinal cord are composed of various types of tissue that perform different functions. Gray matter contains dendrites, neural cells, and axon terminals. White matter contains myelin and axons. The white matter may also be referred to as superficial tissue. This is due to its location in the outer parts of the spinal cord and brain. White matter regulates and transmits nerve signals from the cerebrum to the spinal cord and other brain tissues. Within the spinal cord, white matter functions as a complex network of wiring that carries information throughout the central nervous system. When this white matter in the spinal cord becomes inflamed, it is called leukomyelitis.

Some of the most common causes of this condition are cerebral palsy, multiple sclerosis, and other inherited childhood diseases. When there is inflammation in the white matter of the spinal cord, the effectiveness of a patient's blood-brain barrier becomes compromised. This process allows for further infiltration of the central nervous system by antibodies and peripheral immune cells. This compounded inflammation can damage the protective myelin sheathing that insulates the neural axons and allows for the smooth transmission of signals.

Acute Flaccid Myelitis

Acute flaccid myelitis is the type that affects the gray matter inside an individual's spinal cord. Many cases are caused by a viral infection. Examples include West Nile virus, enteroviruses, adenovirus, and poliovirus. Classic symptoms of this condition include loss of muscle tone, sudden leg or arm weakness, and absent or decreased reflexes.

Sometimes the nerves controlling an individual's neck and head can become inflamed as well. This results in eyelid drooping, speaking difficulties, facial weakness, problems swallowing, and difficulty moving the eyes. It can be difficult to pinpoint acute flaccid myelitis as the cause of associated symptoms. This is because the spinal fluid of affected individuals typically does not contain any causative pathogens. Diagnosis has to be made based on a physical examination, evaluation of the nervous system, and diagnostic imaging of the patient's spinal cord. Treatment usually involves occupational or physical therapy.

Poliomyelitis

Poliomyelitis is a form caused by an infection of a highly transmittable virus. This virus is part of the Picornaviridae family. It infects an individual by invading the oropharynx and then colonizing in their tonsils, neck lymph nodes, Peyer patches, and small intestine. Symptoms begin anywhere from two to thirty-five days following initial exposure. Initially, the poliovirus produces flu-like symptoms for three to five days. It then enters the bloodstream and moves to the central nervous system. Once here, it damages the spinal anterior horn cells. The virus then spreads to the posterior horn cells, hypothalamus, and motor neuron of the thalamus.

This central nervous system invasion causes symptoms of paralysis in multiple parts of the body. It also summons an immune response that characterizes poliomyelitis. This immune response is the congregation of plasma cells, microglia, neutrophils, and other macrophages, which consume cells infected by poliovirus. The result is damage to the white matter of the spinal cord. Severe cases cause respiratory paralysis. Elimination of the infection and rehabilitation of lost nerve and muscle function are the focuses of treatment.

Meningococcal Myelitis

Meningococcal myelitis is inflammation of the spinal cord caused by Meningococci or a type of bacteria with the ability to produce serious infections in the body. It causes meningitis more often than it does myelitis. However, both may occur together. The first symptoms include fever, vomiting, stiff neck, and intense headaches. This type of infection can affect both the white and grey matter of the spinal cord, producing the classic symptoms. In such cases, the inflammation of the spinal cord is caused by a direct infiltration and infection of the spinal cord tissues by the bacteria itself.

However, meningococcal myelitis can also occur when the immune system responds to the bacteria that have invaded tissues elsewhere. This is often seen with meningococcal encephalitis and meningococcal meningitis. The immune system reacts to the bacteria by destroying different types of healthy cells and infected cells in the central nervous system. This process causes severe inflammation in the spinal cord or myelitis precipitated from the meningococci bacteria.

Osteomyelitis

Osteomyelitis is a rare bone infection. It is technically a separate condition, though it can occur alongside another type of myelitis. This infection is usually the result of Staphylococcus aureus, which is a type of staph bacteria. Chronic conditions, such as diabetes, increases an individual's risk of developing osteomyelitis. It is worth noting that the infection can happen in several ways. One is that an infection elsewhere in the body spreads to the bloodstream and travels to the individual's bones. Other sources are infections reaching the bone through surgery or an open fracture.

Symptoms of this condition include fatigue, swelling around the affected bone, fever, nausea, irritability, and lost range of motion. Patients often deal with warmth, tenderness, and redness around the infection site. Most patients receive antibiotics to treat their infection. The antibiotics may be given intravenously in the hospital at first, but patients can transition to oral antibiotics. Severe cases may require surgery to remove infected tissue and bone.