2 Flashcards
1
Q
Antibodies in Myasthenia Gravis
A
- Anti-AChR-> found in 85% patients
- > only in 50% patients with only ocular type - Anti-MuSK (muscle specific kinase) in 10% patients, but in 40% in those without Anti-AChR Ab
- >they predispose to generalized type of MG - Anti-LRP4 ([Low-density] Lipoprotein receptor-related protein 4)
2
Q
Diagnosis of Myasthenia Gravis
A
- Antibodies
- Repetetive nerve stimulation -> decrement of >10%
- EMG single fiber -> blocking and jitter (drganie)
- Edrophonium chloride test
- Ice pack test
- Thymus’ abnormalities
3
Q
Condition that can mimic Myasthenia gravis
A
- Congenital myasthenia
- Drug induced myasthenia ex. Penicillamine
- Lambert-Eaton Myasthenic Syndrome
- Neurasthenia
- Hyperthyroidism (Graves disease)
- Botulism
4
Q
Lambert-Eaton Myasthenic Syndrome causes
A
- > anti P/Q-type calcium channels (85% patients with LEMS)
1. Small-cell lung cancer
-> 33% of LAMS are not assossiated with cancer ->with HLA-B8 or -DR4 haplotypes
5
Q
Treatment of LAMS
A
- Look for a tumor
- AChE, especially Piridostygmine
- 3,4-diaminopyridine -> blocks potassium channel efflux in nerve terminals -> increases action potential duration
- Plasmapheresis
- Immunosupresants or IVIG
6
Q
Myasthenia Gravis treatment
A
- Anticholinesterase
- Immunosupression
- Plasmapheresis
- IVIG
- Thymectomy
7
Q
Anticholinesterase Myasthenia Gravis treatment
A
- Piridostigmine
- Ambenonium
- Neostigmine (Prostigmin)
8
Q
Immunosupression Myasthenia Gravis treatment
A
- Prednisone -> I treatment
- Azathioprine
- Mycophenolate mofetil
- Rituximab
9
Q
Oculomotor Nerve (III) Palsy symptoms
A
- Dilated fixed pupil
- Inability to look up or medialy
- Lateral ocular deviation or “down and out” look
- Diplopia
- Absent accomodation
- Ptosis (of upper lid)
10
Q
Oculomotor Nerve (III) Palsy causes
A
4xI 3xH
- Ischemia
- Intracranial aneurysm
- Head trauma
- Intracranial tumor
- Hemorrhage
- Hereditary (congenital)
- Idiopathic
11
Q
Trochlear Nerve Palsy symptoms
A
- Hypertropia -> upward deviation of the eye (ill eye is higher than opposite eye)-> increases when patient looks down and to opposite side
- Reduced ability to look downward when looking medialy
- Diplopia -> especially when looking down (ex. walking downstairs, reading)
12
Q
Trochlear Nerve Palsy causes
A
- Head trauma
- Congenital
- Ischemic (microvascular)
- Secondary to posterior fossa surgery
- Posterior fossa tumor (rarely)
13
Q
Abducens Nerve (CN VI) Palsy symptoms
A
- Reduced or absent abduction of the eye
- Esotropia -> a form of strabismus in which one or both eyes turns inward
- Diplopia
14
Q
Abducens Nerve (CN VI) Palsy causes
A
- Ischemia (arteriosclerosis, DM, hypertension)
- Increased ICP - intercranial pressure
- Intracranial tumor
- Trauma
- Meningitis
- Demyelination
- Intracranial hypotension (ex. after lumbar puncture)
