Transcript Document

Acute Myelopathies
Darrell Laudate
12/4/09 AM Report
Overview of Acute Myelopathy

Spinal cord dysfunction or myelopathy, can occur
due to a lesion arising within the spinal cord or due
to compression of the spinal cord originating outside
of it
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Frequently devastating, often producing
quadriplegia, paraplegia, and sensory deficits
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Many spinal cord diseases are reversible if
recognized and treated at an early stage
Transverse Myelopathy vs. Myelitis

Transverse Myelopathy refers to clinical
presentation of severe motor, sensory, and
autonomic dysfunction (bowel, bladder, and
sexual abnormalities ) below a spinal cord lesion
due to any acute/ subacute process affecting the
spinal cord, compressive or not
 Often associated with back pain

Transverse Myelitis refers to an inflammatory
process of the grey and white matter of the spinal
cord
Transverse Myelopathies (cont.)

Localization of the lesion depends upon the level of the spinal cord involved
and the extent of the involvement of the various long tracts. In some cases,
there is almost total paralysis and sensory loss below the level of the lesion,
others only partial loss
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If cervical area is involved, all four limbs may be involved and there is risk
of respiratory paralysis (segments C3,4,5 to diaphragm)
 Lhermitte's sign: an electric shock-like sensation down the neck,
back, or extremities that occurs with bending of the neck
Lesions of the lower cervical (C2-T1) region will cause a combination of
upper and lower motor neuron signs in the upper limbs, and exclusively
upper motor neuron signs in the lower limbs.
A lesion of the thoracic spinal cord (T1-12) will produce a spastic
paraplegia.
A lesion of the lower part of the spinal cord (L1-S5) often produces a
combination of upper and lower motor neuron signs in the lower limbs
Upper vs Lower Motor Neuron Lesions

Lower motor neuron lesion is a lesion which affects nerve fibers traveling from the
anterior horn of the spinal cord to the relevant muscle(s)
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Associated with areflexia
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leads to flaccid paralysis (paralysis accompanied by muscle loss)
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Upper motor neuron lesion is a lesion of the neural pathway above the anterior horn
cell or motor nuclei of the cranial nerves and are marked by:
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Spasticity, increase in tone in the extensor muscles (lower limbs) or flexor muscles
(upper limbs)
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Clasp-knife response where initial resistance to movement is followed by relaxation
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Weakness in the flexors (lower limbs) or extensors (upper limbs), but no muscle
wasting
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Brisk tendon jerk reflexes
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Babinski or Hoffman sign is present
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increase deep tendon reflex
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Pronator drift
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(Spinal Shock - loss of sensation accompanied by motor paralysis with initial loss but
gradual recovery of reflexes
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Occurs following a spinal cord injury, thus what may have looked like a lower motor
neuron lesion can later reveal itself to be an upper motor lesion)
Important Dermatomal Landmarks
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C2 - posterior half of the skull cap
C3 - area correlating to a high turtle neck shirt
C4 - area correlating to a low-collar shirt
C6 - (radial nerve) 1st digit (thumb)
C7 - (median nerve) 2nd and 3rd digit
C8 - (ulnar nerve) 4th and 5th digit, also the funny bone
T4 - nipples.
T5 - Inframammary fold.
T6/T7 - xiphoid process.
T10 - umbilicus (important for early appendicitis pain)
T12 - pubic bone area.
L1 - inguinal ligament
L4 - includes the knee caps
Evaluation of suspected myelopathy

Imaging is indicated in all patient with suspicion for myelopathy

MRI is generally the most appropriate study as it images the spine,
paraspinal region, and spinal cord; also may reveal evidence of intrinsic
lesions
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most patients with suspected cord compression should have total spinal
cord imaging
sole imaging of the lumber spine is often ordered with cord compression
suspicion, but recall the spinal cord ends at L1, thus visualization of the
spinal cord is not possible with a lumbar MRI alone
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lumbar MRI is useful however to exclude cauda equina
compression (lower extremity weakness and sensory and
bladder disturbances without upper motor neuron signs)
Exceptions may include pts with upper and lower extremity symptoms as
cervical localization is likely -> Cervical MRI
Other Studies
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Lumbar Puncture
Serologic Studies as clinically indicated
CT myelogram may be beneficial in
patients with suspected inflammatory
or demyelinative lesions of the spinal
cord
Noncompressive Myelopathies
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Vascular
 Arteriovenous malformation
 Antiphospholipid syndrome and other hypercoagulable states
Inflammatory
 Multiple sclerosis
 Neuromyelitis optica (Devic’s Disease)
 Transverse myelitis (idiopathic)
 Sarcoidosis
 Vasculitis
Infectious/Postinfectious
 Viral: VZV, HSV-1 & -2, CMV, HIV, HTLV-I, enteroviruses,
flaivaviruses
 Bacterial and mycobacterial: Borrelia, Listeria, syphilis, Mycoplasma
pneumoniae
 Parasitic: schistosomiasis, toxoplasmosis
Metabolic
 Vitamin B12 deficiency (subacute combined degeneration)
 Copper deficiency
Compressive Myelopathies
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Cervical spondylosis
Epidural, intradural, or intramedullary neoplasm
Epidural abscess
Epidural hemorrhage/hematoma
Herniated disc
Posttraumatic compression by fractured or displaced vertebra or
hemorrhage
Clinical criteria alone cannot distinguish spinal cord
compression and intrinsic cord lesions
Acute Viral Myelitis
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Two Forms
 Enteroviruses (poliovirus, coxsackie virus, and enterovirus 71), Flaviviruses
(West Nile virus and Japanese encephalitis virus) have been known to target
the gray matter (Anterior horn cells) of the spinal cord, producing acute lower
motor neuron disease.1
 usually accompanied with fever, headache, and meningismus
 produces asymmetrical flaccid weakness with reduced or absent reflexes
and few sensory symptoms or signs
 MRI often shows hyperintensities in the anterior horns of the spinal cord
on T2-weighted imaging Cerebrospinal fluid (CSF) analysis
demonstrates a moderate pleocytosis
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These features help to distinguish this form of viral myelitis from GuillainBarré syndrome, which usually produces symmetric deficits, with no MRI
abnormalities, and is associated with elevated CSF protein levels without
pleocytosis.
Acute Viral Myelitis
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CMV, VZV, HSV I &II, HCV, and EBV are associated with a second
form of viral myelitis has clinical and diagnostic test features that
are similar to transverse myelitis
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Association between the myelitis and the virus is not always
clear, some may represent post-infectious transverse myelitis,
others, a positive polymerase chain reaction (PCR) test in the
CSF suggests that the myelitis is directly related to the viral
infection
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Treated with Herpes zoster, HSV, and EBV myelitis are treated
with intravenous acyclovir (10 mg/kg q8h) or oral valacyclovir
(2 gm tid) for 10–14 days; CMV with ganciclovir (5 mg/kg IV
bid) plus foscarnet (60 mg/kg IV tid), or cidofovir (5 mg/kg per
week for 2 weeks).2
Other Infectious Myelopathies
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HIV
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More of a chronic myelopathy, Often found mostly in late stages of AIDS and
associated with AIDS related dementia in half
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slowly progressive spastic paraparesis is accompanied by loss of vibration and
position sense and urinary frequency, urgency, and incontinence
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CSF may show nonspecific protein elevation
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ART may reverse the symptoms3
Bacterial
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Mycoplasma (acute and post infectious), Listeria monocytogenes
TB
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via secondary cord compression from verterbral osteomyelitis, aka Pott’s disease
Also via compressive tuberculomas
Lyme disease
 Cases have been described in which clinical and MRI features resembling
acute transverse myelitis have been attributed to Lyme disease.4
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CSF in these cases typically demonstrates a lymphocytic pleocytosis and elevated
protein
Schistosomiasis (in endemic areas)
Tabes Dorsalis (Locomotor Ataxia)
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Form of tertiary neurosyphilis in which the nerves of the dorsal (or posterior)
columns degenerate
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Loss of sense of position (proprioception), vibration, and discriminative
touch
Latency period of 3-20 years
Cardinal signs of tabes are loss of reflexes in the legs; impaired position and
vibratory sense; Romberg's sign
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also:
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bilateral Argyll Robertson pupils
fleeting and repetitive lancinating pains, primarily in the legs
Paresthesias/ formincation
visceral crisis (Bladder disturbances, and acute abdominal pain with vomiting
personality changes, dementia, deafness, visual
skeletal musculature is hypotonic due to destruction of the sensory limb of the
spindle reflex
Ataxia of the legs and (tabetic) gait due to loss of position sense occurs in half
of patients
Tabes dorsalis (cont.)
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VDRL & RPR (nontreponemal tests) may be nonreactive in late neurosyphilis
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If suspcion suspicion for neurosyphilis, serum FTA-ABS or TPPA (treponemal
tests) are preferred
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CSF may be completely normal in tabes dorsalis, or may show mild
lymphocytic pleocytosis with 10 to 50 cells/microL and protein concentrations
of 45 to 75 mg/dL.
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Syphilitic meningovascular myelitis can represent an earlier form of syphilis
infection
 focal inflammation of the meninges can secondarily affect the adjacent
anterior spinal artery thus result in a CVA or spinal cord infarction
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Treatment - Penicillin G 3 to 4 million units IV every four hours or 24 million
units continuous IV infusion for 10 to 14 days
Connective tissue Associated
Myelopathies
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SLE
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May be the initial feature but onset is usually present with other active lupus signs.
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thought to be due to an arteritis, with resultant ischemic necrosis of the spinal cord
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ANA, ds-DNA, anti-Sm, Anti-neuronal (may correlate with active CNS lupus)
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Has been associated with antiphospholipid antibodies in some studies but not all.5
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Treatment: Prednisone (1.5 mg/kg per day), plasmapheresis, and cyclophosphamide.6
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Antiphospholipid antibodies a may also benefit with warfarin as well as steroids and
immunosuppressive treatment.7
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Mixed connective tissue disease
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Sjogren's syndrome (antibodies to the Ro/SSA or La/SSB)
Scleroderma (ANA, anti-Scl-70, anti-centromere (ACA), anti-RNA polymerase III, and anti-beta2glycoprotein I antibodies)
Ankylosing spondylitis
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Acute myelopathy will typically occur in the setting of fracture of ankylosed spine or atlantoaxialaxial subluxation
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cauda equina sydrome rare but associated with long standing disease
Rheumatoid arthritis
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atlantoaxial subluxation, atlantoaxial impaction, and/or subaxial subluxation
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Rarely associated with CNS vasculitis and more rarely with myelopathy from vasculitis
Sarcoid
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Neurosarcoidosis
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Typically occur perivascularly, but they can be extramedullary or
intramedullary, and can involve the cauda equina.
Occurs 5% of Sarcoid patients
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MRI signal abnormalities are not specific
 neurosarcoid lesions can appear similar to transverse myelitis or
can resemble a tumor
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CSF profile consists of variable lymphocytic pleocytosis; oligoclonal
bands are present in one-third of case
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Generally treated with corticosteroids and other immunomodulatory
agents and can improve
B12 Deficiency (subacute combined
degeneration of spinal cord)
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Damage to peripheral nerves caused by demyelination and irreversible
nerve cell death.
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Symptoms include
 paresthesias in the hands and feet
 loss of vibration and position sensation
 progressive spastic and ataxic weakness
 Loss of reflexes due to an associated peripheral neuropathy in a
patient who also has Babinski signs, is an important diagnostic
clue
 Optic atrophy and irritability or other mental changes may be
prominent in advanced cases
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This myelopathy tends to be diffuse rather than focal; signs are
generally symmetric and reflect predominant involvement of the
posterior and lateral tracts, including Romberg's sign
B12 deficiency (cont.)
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Usually established by the presence of decreased Vit B12
level
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in the cases of low-normal B12, the presence of elevated MMA
and homocysteine levels may be useful
Treatment: 1mg Cbl IM once daily for 1 week, followed by
1 mg IM every week for four weeks
 if the underlying disorder persists, 1 mg every month
for the remainder of the patient's life.
Hypocuric Myelopathy (Copper
Deficiency)
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Very similar to subacute combined degeneration
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Progressive spasticity, severe gait abnormalities including ataxia,
and a neuropathy.
 Also associated with anemia and neutropenia in certain patients
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More common after gastric bypass, also with zinc supplementation
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Diagnosis usually confirmed with low levels of serum copper are found
and often there is also a low level of serum ceruloplasmin
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Symptoms are potentially reversible with copper supplementation and
reversal of underlying cause
Multiple Sclerosis
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Most common autoimmune inflammatory demyelinating disease
of the CNS
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Women of Northern European descent who are of child-bearing
age.
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Histological examination of active plaques reveals perivascular
infiltration of lymphocytes (predominantly T cells) and
macrophages with occasional plasma cells. Perivascular and
interstitial edema may be prominent.
Multiple Sclerosis (cont.)
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Multiple sclerosis (MS) is a clinical diagnosis. There are no clinical
findings that are unique to this disorder, but some are highly
characteristic
Older criteria considered clinical characteristics and a number of
laboratory studies
 these findings were then used to place patients in categories
ranging from clinically definite to laboratory supported definite to
clinically probable to laboratory supported probable MS
McDonald criteria focus on a demonstration with clinical, laboratory
and radiologic data of the dissemination of MS lesions in time and
space, also incorporated specific MRI findings into the diagnostic
scheme
A diagnosis cannot be made until other possible conditions have been
ruled out and there is evidence of demyelinating events separated
anatomically and in time
Multiple Sclerosis (cont.)
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CSF
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oligoclonal bands using isoelectric focusing is the most important diagnostic CSF
study when determining a diagnosis of MS
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2/3 will have normal leukocyte count
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Will also see elevation of the CSF immunoglobulin level relative to other protein
components, suggesting intrathecal synthesis, generally IgG
MRI
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Cerebral or spinal plaques that are ovoid and hyperintense on proton density and T2-weighted
studies, and they are hypointense (if visible at all) on T1-weighted images.
Conventional T2-weighted MRI techniques may underestimate MS plaque size
and burden, Diffusion tensor imaging and MR spectroscopy may correct this
Evoked potentials (EPs): CNS electrical events generated by peripheral stimulation of
a sensory organ)
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Can detect abnormal CNS function that may be clinically undetectable or help
define the anatomical site of the lesion in tracts not easily visualized by imaging
(e.g., optic nerves, dorsal columns).
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>50cells/microliter occurs only rarely and should raise suspicion of alternative
etiology
Neuromyelitis optica (Devic’s Disease)
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Autoimmune, inflammatory disorder in which the optic nerves and spinal cord are
targeted but may also affect the brain,
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Resembles multiple sclerosis (MS) as it has varying degrees of weakness or paralysis in
the legs or arms, loss of sensation (including blindness), and/or bladder and bowel
dysfunction.
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Lesions are different from those observed in MS in that the attacks appear to be not
mediated by the immune system's T cells but rather by antibodies called NMO-IgG that
target aquaporin 4 of astrocytes.6
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Acts as a channel for the transport of water across the cell membrane
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Found in the processes of the astrocytes that surround the blood-brain barrier,
 This blood-brain barrier is weakened in Devic's disease, but it is unclear how
NMO-IgG immune response leads to demyelination
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Criteria: Optic neuritis, Myelitis, and one of the following:
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MRI evidence of a contiguous spinal cord lesion three or more segments in length,
or
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Seropositivity for NMO-IgG
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Treatment: Steroids, Cytoxan, PLEX, +/- Rituximab
Cervical Spondylosis

Chronic degenerative and hypertraphic changes that involve
intervertebral disks, vertebral bodies, facet joints, and ligaments
 if severe, can result in narrowing of cervical spinal canal and
cause spinal cord compression
 In many case series, cervical spondylotic myelopathy is the most
common cause of myelopathy, particularly in older adults
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Cervical Spondylotic Myelopathy
 clinical syndrome associated with spondylosis but with spinal cord
dysfunction
 commonly in pts > 55y, perhaps most common form of myelopathy
 insidious onset of numbness, parathesias in upper extremities,
spastic or stiff-legged gait that is often not associated with pain
 surgical decompression is generally used to treat if symptomatic,
although there is no evidence from RCT proving the efficacy of this
therapy7
Metastatic Disease to Spinal Cord
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Oncologic emergency
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usually requring treatment with corticosteroids (usually
dexamethasone), and emergent radiation therapy or surgery
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indications for decompressive surgery for metastatic epidural
spinal cord compression includes: when tissue diagnosis is
needed, presence of spinal instability, or tumor is known to be
radioresistant
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One study showed patients who underwent anterior
decompressive surgical resection of metastatic epidural spinal
cord compression due to cancer had better ambulatory
outcomes than with radiation therapy alone.8
Epidural Abscess
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Rare, occurring in only 1 patient per 10,000 admitted to the hospital.9
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Most common pathogen is Staphylococcus aureus, which accounts for
about two-thirds of cases 9
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Typically originate via contiguous spread from infections of skin and
soft tissues or as a complication of spinal surgery and other invasive
procedures, including indwelling epidural catheters.
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Expected back and/or radicular pain usually but not always
accompanied systemic signs of infection
MRI preferred test
Requires emergent surgical decompression and antibiotic therapy are
indicated to treat epidural abscess
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Spinal Cord Infarction
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Rare compared with CVA
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Most frequently caused by surgical procedures and pathologies
affecting the aorta
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May also occur in the setting of vascular risk factors or aortic
disease
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Presents with sudden spinal cord dysfunction that typically
corresponds to the territory of the anterior spinal artery
 Weakness and pinprick loss below the level of the infarction but
sparing vibration and position sense
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No treatment available and prognosis is variable and dependent upon
severity of presenting deficit
Dural AVM of Spinal Cord

Rare cause of ischemic spinal cord dysfunction
 Obstructs venous outflow of the spinal cord
 May progress over months to years

Surgical obliteration of the fistula can potentially
reverse this condition
References
1)
Solomon et al. Infectious causes of acute flaccid paralysis. Curr Opin Infect Dis. 2003 Oct;16(5):375-81
2)
Hauser et al. "Chapter 372. Diseases of the Spinal Cord" (Chapter): Harrison's Principles of Internal Medicine, 17e:
http://www.accessmedicine.com/content.aspx?aID=2904373.
3)
Meurs et al. Acute transverse myelitis as a main manifestation of early stage II neuroborreliosis in two patients. Eur Neurol 2004;
52:186.
4)
Staudinger et al. Remission of HIV myelopathy after highly active antiretroviral therapy. Neurology 2000; 54:267.
5)
Lennon et al. IgG marker of optic-spinal multiple sclerosis binds to the aquaporin-4 water channel. J. Exp. Med. 2005. 202 (4): 473–7.
6)
Transverse myelitis as the first manifestation of systemic lupus erythematosus or lupus-like disease: good functional outcome and
relevance of antiphospholipid antibodies. AU D'Cruz DP; Mellor-Pita S; Joven B; Sanna G; Allanson J; Taylor J; Khamashta MA;
Hughes GR SO J Rheumatol 2004 Feb;31(2):280-5.
7)
Transverse myelopathy in systemic lupus erythematosus: an analysis of 14 cases and review of the literature. AU Kovacs B; Lafferty
TL; Brent LH; DeHoratius RJ SO Ann Rheum Dis 2000 Feb;59(2):120-4.
8)
Acute transverse myelopathy in systemic lupus erythematosus: clinical presentation, treatment, and outcome. AU Mok CC; Lau CS;
Chan EY; Wong RW SO J Rheumatol 1998 Mar;25(3):467-73
9)
Porter et al. Endocrine and reproductive manifestations of sarcoidosis. QJM 2003; 96:553.
10)
McCormick et al. Cervical Spndylotic myelopathy: make the difficult diagnosis, then refer to surgery. Cleve Clin J Med. 2003;70:899904
11)
Patchell et al. Direct decompressive surgical resection in the treatment of spinal cord compression caused by metastatic cancer: a
randomised trial. Lancet. 2005;366:643.
12)
Darouiche, RO. Spinal epidural abscess. N Engl J Med 2006; 355:2012.