Infectious myelopathies.

Every genus of microorganism, as well as prions, has been associated with disease of the spinal cord. The spectrum of pathogens resulting in myelopathy varies with the population. Myelopathy is uniquely associated with certain retroviruses, particularly HIV type 1 and human T-cell lymphotropic virus type I, but the myelopathies that occur with these viruses are chiefly limited to "at risk" populations. In the immunocompromised population, a diverse array of pathogens may cause spinal cord disease, especially viruses from the Herpesviridae family, most notably cytomegalovirus and varicella-zoster virus. The prototypical myelopathy resulting from bacterial infection is tabes dorsalis, but this disorder is vanishingly rare in the modern era. In developing countries, Mycobacterium tuberculosis and schistosomiasis remain significant causes of myelopathy.