Infectious Myelopathies

PURPOSE OF REVIEW: This article reviews bacterial, viral, fungal, and parasitic pathogens associated with myelopathy. Infectious myelopathies may be due to direct infection or parainfectious autoimmune-mediated mechanisms; this article focuses primarily on the former. RECENT FINDINGS: Some microorganisms exhibit neurotropism for the spinal cord (eg, enteroviruses such as poliovirus and flaviviruses such as West Nile virus), while others are more protean in neurologic manifestations (eg, herpesviruses such as varicella-zoster virus), and others are only rarely reported to cause myelopathy (eg, certain fungal and parasitic infections). Individuals who are immunocompromised are at increased risk of disseminated infection to the central nervous system. Within the last few years, an enterovirus D68 outbreak has been associated with cases of acute flaccid paralysis in children, and emerging Zika virus infection has been concurrent with cases of acute flaccid paralysis due to Guillain-Barré syndrome, although cases of myelitis have also been reported. Associated pathogens differ by geographic distribution, with myelopathies related to Borrelia burgdorferi (Lyme disease) and West Nile virus more commonly seen in the United States and parasitic infections encountered more often in Latin America, Southeast Asia, and Africa. Characteristic CSF and MRI patterns have been identified with many of these infections. SUMMARY: A myriad of pathogens are associated with infectious myelopathies. Host factors, geographic distribution, clinical features, CSF profiles, and MRI findings can assist in formulating the differential diagnosis and ultimately guide management.