Wahba Part 2 - Myelopathy Flashcards
Pathogenesis of Lambert-Eaton
Dysfunction of presynaptic Ach release 2/2 Abs against P/Q type voltage-gated Ca channels
Symptoms of Lambert-Eaton
Generalized fatigue+weakness, myalgia, muscle tenderness, stiffness, strength improves w/ exercise, metallic taste in mouth and dryness, orthostasis, constipation, impotence, DTR absent/diminished
Epidemiology of Lambert-Eaton
60% have small cell carcinoma, 90% have Abs against P/Q type VGCC, 50% have Abs against N type VGCC
How to dx L-E
Compound muscle action potential
Treatment of L-E
1st evaluate for malignancy, guanidine hydrochloride inhibits mitochondrial Ca uptake (causes myelosuppresion)
Location of lesion of cauda equina syndrome
Affects nerve roots between T10, lower border of L1
Signs and symptoms of cauda equina syndrome
Root compression, paraplegia, BL absence of ankle reflex, urinary retention, post-void residual incontinence, decreased anal tone and fecal incontinence, sexual dysfunction, saddle anesthesia
Etiologies of cauda equina syndrome
Traction and pelvic fractures following gunshot injuries, MVA, and falls
Imaging in cauda equina syndrome
CT, MRI
Treatment of cauda equina syndrome
Surgical decompression, spinal nerve reconstruction, repair of ventral nerves and nerve transfer
When to MRI cauda equina syndrome
Weakness+reflexes+radiculopathy signs
Red flags of myelopathy
Loss of weight+night sweats+endemic areas+TTP on spine
What to do if no red flags
Give muscle relaxer/NSAID
Features of acute myelopathy
Acute onset of weakness+sensory loss+ANS dysfunction (urinary retention), absence of other cortical findings
CSF findings in acute myelopathy
Mild-moderate lymphocytic pleocytosis, increase protein, normally or mildly decreased glucose
Differential for myelopathy
Vascular - SC infarction, bacterial/fungal/parasitic/viral infections, Autoimmune - SLE, MS, Structural - compression, nucleus pulposus herniation
S and S of myelopathy
Weakness, sensory loss @ level, autonomic dysfunction, loss of anal sphinter tone+cremasteric reflex+anal wink+bulbocavernosus response, urinary retention, bowel dysfunction
Features of transverse myelitis
Complete axial plane transection of cord; all sensory/motor loss below the lesion; viruses most likely etiology
Features of partial myelitis
Brown Sequard - ipsilateral UMN signs, ipsilateral loss of tactile, vibration, propioception sense, C/L loss of pain and temp (pinprick demarks 1-2 levels below lesion), LMN signs at level of lesion, Horner’s (above T1)
Partial myelitis - acute vs chronic?
Acute has increased tone and reflexes; chronic has spasticity w/ pathologic reflexes
Etiology of poliomyelitis
Poliovirus, West Nile, Enterovirus
Features of poliomyelitis
Weakness of LMN, occurs w/in days of acute viral syndrome including meningitis; weakness is acute, asymmetric, mostly in legs; bladder dysfunction; loss of tone+reflexes; sensory spared
CSF findings and Dx of polio
mild-mod lymphocytic pleocytosis, increased protein, increased IgG synthesis, viral PCR and Ab titers; also get MRI spine (swollen+enhance w/ gadolinium on T1+high signal on T2)
Antiviral treatment for polio
Acyclovir (EBV, VZV, HSV), Ganciclovir/foscarnet (CMV), baclofen +/- BZD +/- tizanidine (chronic spasticity)
