12)
D) Multiple sclerosis
"A pale disc is characteristic of long-standing optic neuropathy"
Multiple Sclerosis (MS)
Autoimmune demyelinating disease of the CNS. Genetic predisposition along with environmental triggers may count for etiology. Higher risk in white people. Plaques of MS are glyotic lesions in the white matter clustering around the lateral ventricles, spinal cord, brain stem, and cerebellum.
Essentials of diagnosis
1. History and P/E usually reveal evidence of OPTIC NEURITIS ("Pale Disc"), intranuclear Ophthalmoplegia, HEMIATAXIA, HEMISENSORY DEFICIT, HEMIPARESIS, or TRIGEMINAL NEURALGIA.
2. Lab tests:
MRI is most sensitive (> 90%) for white matter disease.
CSF : Oligoclonal bands are the pathologic features.
Evoked potentials involve visual, auditory, and brainstem origins.
3. Diagnosis:
In most cases , history , P/ E, and MRI scan can establish the accurate Dx.
4. Relapsing forms: Occasional attacks followed by near-recovery. Gradual deficits may develop.
Treatment
1. ACUTE ATTACK: High-dose STEROIDS I.V. can shorten the duration & delay next attack.
2. Symptomatic- Treatment
Baclofen/ Zanaflex for Spasticity
Carbamazepine for Pain
Amitriptyline for Depression with fatigue
Cholinergics for urinary retention
Anticholinergics for urinary incontinence
3. For worsening relapsing cases:
Immunosuppressants (cyclosphosphamide, etc), IV Ig, and plasmapheresis can be used.
4. For prophylaxis and relapse reduction:
Immunomodulators (interferonb1a, interferonb1b, or Copolymer-1) may be helpful.
Differential diagnosis
Other Myelinopathies: Vit-B 12 deficiency, Vit-E deficiency, abetalipoproteinemia, syringomyelia, adrenoleukodystrophy, Tabes dorsalis, etc.
Gong MD, Yale (2013-02-05). Yale-G's Refined Clinical Review for USMLE Step 2 & 3 (New Edition) (Kindle Locations 4910-4924).
www.usmle-yaleg.com. Kindle Edition.
