Flashcards in CM: MS and Related Deck (22):
What is MS?
autoimmune process leading to demyelination and neurodegeneration
What are the statistics involving ambulation at 10 yrs?
50% will require cane
15% will require wheelchair
What percentage of pts with MS will develop secondarily progressive MS (SPMS) after 10 yrs?
50% of RRMS
What are the four characteristics that predict a severe course of MS?
motor and cerebellar symptoms
disability after the first attack
short time interval between attacks
lesion burden on MRI (high load, or change in load w/i first yr)
What are the symptoms of RRMS?
relapses comprised of visual blurring (optic neuritis), diplopia, vertigo, numbness, paresthesias, and weakness (myelopathy)
incomplete healing after attack --> slight residual symptoms, cumulative disability in long term
What are the symptoms of SPMS?
more pronounced, steady, progressive decline in fxn, w or w/o superimposed relapses
ambulation difficulties, bladder, bowel and sexual dysfunction = myelopathic features
= transition from inflammatory to degenerative
What are the symptoms of PPMS?
gradual decline from onset, myelopathic features
progressive relapsing MS is subset - rare relapses on slow progression, paucity of MRI lesions, F:M = 1:1, lack of response to immunomodulatory agents used in RRMS
What are the basics of diagnosing MS?
lesions in time and space
McDonald criteria - combo of clinical hx, PE, MRI and paraclinical tests (evoked potentials, CSF)
spinal cord lesions
IV gadolinium enhancement - breakdown of BBB, differentiates active from chronic lesions
What is the classic MRI finding in MS?
PERIVENTRICULAR, perpendicular, ovoid lesions
infratentorial lesions = Dawson's fingers, can find on FLAIR
What are evoked potentials?
measuring slowing of electrical signal propagation can indicate demyelination
better w auditory, visual, and sensory neural
somatosensory and brainstem auditory have low sensitivity
What is the clinically isolated syndrome of MS?
one attack and no evidence of second relapse
one symptom or abnormality w/o evidence of classic lesions
majority who will develop MS have lesion on MRI at time of first event
present w spinal cord syndrome, optic neuritis, or brainstem symptoms
What are three main presenting symptoms of MS?
What is optic neuritis?
inflammation and demyelination of optic nerve --> blurred vision, blindness, pain w ocular movement, color desaturation, afferent pupillary defect = Marcus Gunn pupil (affected lacks direct response), disc usually normal but pallor can happen with time
What is transverse myelitis?
numbness and paresthesias, weakness, spasticity, pain, bowel bladder and sexual dysfunction
predilection for lesions in posterior columns
What is Lhermitte's sign?
electrical sensation down arms or legs w flexion of neck due to inflammation of cervical spinal cord
common complaint of transverse myelitis
What is intranuclear ophthalmoplegia?
lesions in brainstem typically in periventricular pontine tegmentum
lesions of MLF produce classic adductor slowing of contralateral eye (intact abduction)
What are some differences between MS and other autoimmune disorders that can present similarly?
lesions typically more peripheral in deep white matter in others
exceptions = sarcoid - lesions can be in periventricular areas, tumors - lesions can be in CC
What are the basics of treatment of MS?
IV steroids for relapses and optic neuritis
preventative - immunomodulators (interferon, monoclonal antibodies, IVIG/plasmapharesis) and immunosuppressives
What can cause relapse w symptom exacerbation and what is seen on MRI?
heat, fatigue, UTI - inciting factor should be IDed and improvement should be w/i 1-2 days of Rx
lack of new lesions, gadolinium enhancement
What is neuromyelitis optica?
bilateral optic neuropathy and myelitis
serum Ab against aquaporin 4 (NMO-IgG)
brain MRI usually has few hyperintensities and myelitis usually multi-segmental
What is acute disseminated encephalomyelitis (ADEM)?
multiple enhancing lesions in brain w multifocal symptoms, typically monophasic course
often following vaccination or viral inf
rx = corticosteroids