MULTIPLE SCLEROSIS

A 35 year old white female presents with multiple attacks of eye pain with movements of her eyes and unilateral vision impairment starting about 4 years ago at which time she was diagnosed with optic neuritis. The episodes generally last only 1-2 weeks and then disappear with apparently complete recovery. In the past 6-9 months she has had several episodes of urinary incontinence resulting in bed-wetting. Physical exam reveals nystagmus, swollen right optic nerve with decreased visual acuity. Deep tendon reflexes are asymmetric and hyperactive, and sensory exam is normal. She exhibits spastic gait. Ancillary investigations show:

CSF- protein 68 mg/dl, glucose 55 mg/dl, lymphocytic pleocytosis, elevated myelin basic protein, negative Lyme titer, and oligoclonal bands present.

Visual evoked potentials show prolonged latent interval after visual stimulation

CT shows "plaques" in the white matter of both hemispheres:

1-The characteristic location of the lesions in this disease is/are:

A-Cortical ribbon

B-Periventricular white matter

C-Involvement of all the white matter

D-Subcortical white matter

E-All of the above

ANSWER: B

2-This disease is:

A-A specific type of encephalitis

B-A demyelinating process

C-An infectious disease

D-An inborn error of metabolism

E-None of the above

ANSWER: B

3-Microscopically there is:

A-Loss of neurons

B-Myelin breakdown with macrophages and inflammatory cells

C-Loss of pigment of the locus ceruleus

D-All of the above

E-None of the above

ANSWER: B

4-This lesion may be demonstrated with a special stain:

A-GMS for fungi

B-Luxol fast blue PAS stain for myelin

C-Ziehl-Neelsen for acid fast mycobacteria

D-Bielschowsky for neuritic plaques and tangles

E-None of the above

ANSWER: B

5-The entity described above is:

A-Parkinson’s disease

B-Huntington’s chorea

C-Alzheimer’s disease

D-Multiple sclerosis

E-None of the above

ANSWER: D

6. The factor(s) implicated in the pathogenesis of this process is/are:

A. Environmental, since the incidence increases with greater distance from the equator.

B. Genetic, because there is a significant increased risk of developing this disease in first degree relatives

C. Possibly autoimmune, as there is evidence of myelin protein antibody- mediated damage

D. All of the above

ANSWER: D