Transverse myelitis is a demyelinating (loss of the fatty tissue around the nerves) disorder of the spinal cord. It may occur alone or in combination with demyelination in other parts of the nervous system. Onset of the disorder is sudden. Symptoms may include low back pain, spinal cord dysfunction, muscle spasms, a general feeling of discomfort, headache, loss of appetite, and numbness or tingling in the legs. Transverse myelitis may be caused by viral infections, spinal cord injuries, immune reactions, or insufficient blood flow through the blood vessels in the spinal cord. It may also occur as a complication of such disorders as optic neuromyelitis, multiple sclerosis, smallpox, measles, or