Myelopathy

Background

• Broadly speaking, any pathologic process affecting the spinal cord
• Usually classified by time from onset to maximum deficit as acute (within 21 days), subacute (weeks to months), or chronic (months to years)

Etiologies

Acute

Etiology	Onset	Diagnostic Clues
Infection: Bacterial
abscess	acute	recent surgical or dental procedure
Lyme disease	acute	tick exposure, history of erythema migrans
tuberculosis	chronic, can be acute	TB risk factors
syphilis	acute	myelitis possible, as well as meningovascular disease causing spinal cord infarction
Infection: Viral
CMV	acute	immunocompromised
Enterovirus	acute	more often in children and immunocompromised adults
EBV	acute	recent or concurrent mononucleosis
HSV	acute	myelitis, radiculitis, or myeloradiculitis, often with lumbosacral involvement
HIV	acute or chronic	acute during acute infection, chronic as a result of advanced HIV
HHV-6 and HHV-7	acute	transplant patients
JC virus	acute	rare, even in immunocompromised
poliovirus	acute	acute flaccid myelitis, with or without bulbar or autonomic dysfunction
rabies	acute	recent exposure
VZV	acute	with or without rash
WNV	acute	occurs in 5-10% of neuroinvasive cases; can be concurrent with acute flaccid paralysis or meningoencephalitis
Zika virus	acute
Infection: Other
Cryptococcus and other fungi	chronic
neurocysticercosis	chronic	brain more common than spinal cord involvement
schistosomiasis	acute	fresh water exposure; may have myelitis or myeloradiculitis
toxoplasmosis	acute	exposure to raw or undercooked meat
Mechanical Injury
traumatic	abrupt	recent trauma or motor vehicle collision
decompression sickness	acute, rarely delayed	recent decompression (diving, flying, hyperbaric chamber)
spondylotic	chronic, possibly worsening with trauma	degenerative disc disease
surfer's myelopathy	hyperacute	surfer with history of back hyperextension
Iatrogenic
chemotherapy	variable	recent intrathecal chemotherapy, particularly cytarabine and methotrexate
immune checkpoint inhibitor	variable, often acute	recent treatment with immune checkpoint inhibitor
post-surgical	hyperacute	recent spinal or aortic surgery
radiation myelopathy	chronic, but can deteriorate quickly	recent spinal cord radiation
Demyelination
AQP4-IgG	acute	mostly middle-aged women, often with optic neuritic
MOG-IgG	acute	adolescents to young adults, often with optic neuritis
multiple sclerosis myelitis	acute	mostly young woman; most common myelitis
Other Immune-Mediated
connective tissue disease	acute	most young to middle-aged women; findings of other disease, including Behçet disease, lupus, Sjögren syndrome
GFAP-IgG	chronic, can be acute	with meningoencephalitis, optic disc edema, and/or tremor, possibly a flu-like prodrome
neurosarcoidosis	acute in 20%	with or without systemic sarcoidosis
paraneoplastic	chronic, can be acute	known cancer or cancer risk factors
Neoplastic
primary spinal cord neoplasms, including astrocytoma and ependymoma	chronic, can be acute	most common neoplastic cause
primary intramedullary lymphoma	chronic, can be acute	immunocompromised
metastasis	acute	known solid-organ cancer, particularly lung and breast
Toxic or Metabolic
biotinidase deficiency	variable	usually children; often with vision loss
vitamin B12, vitamin E, or copper deficiency	chronic, can be acute	history of gastric bypass, zinc supplementation, pernicious anemia, or malabsorption
cocaine	hyperacute	recent exposure
heroin	acute	recent exposure
lathyrism and konzo	acute to subacute	malnutrition, ingestion of cassava or grass pea
Vascular
spinal aortovenous fistula	acute in 20%	worsening after exertion or steroids
ateriovenous malformations, vacernous malformation	variable	variable
epidural hematoma	acute	bleeding diathesis, trauma, postsurgical
spinal cord infarction	hyperacute	vascular risk factors
fibrocartilaginous embolism	hyperacute	may have a triggering event with valsalva or heavy lifting

Further Reading

• Evaluation and Management of Acute Myelopathy. Semin Neurol. 2021 Oct;41(5):511-529. doi: 10.1055/s-0041-1733792. Epub 2021 Oct 7. PMID: 34619778.