Myasthenia Gravis/MS/Guillain-Barre syndrome Flashcards
What is the cause of MG
-autoimmune disorder resulting in the reduction of the number of acetylcholine receptor sites at the neuromuscular junction
Incidence of MG
incidence peaks in the 3rd decade for females and in the 5th and 6th decades for males
-occurs more commonly in women
Traits unique to MG that not often seen in MS
- ptosis ** (not seen in much else)
- diplopia ** (but also in Guillian and ms)
- dysarthria
- dysphagia
- extremity weakness and visual changes **
- fatigue
- respiratory difficulty **
- sensory modalities and DTRs are normal
- weakness worse after exercise and better after rest
labs and diagnostics of MG
- antibodies to acetylcholine receptors (AchR-ab) are found in 85% of patients **
- tensilon test may be used to differentiate a myasthenia vs cholinergic crisis (if symptoms worsen after giving it know had cholinergic crisis)
Management of MG
Neuro referal
- anticholinesterase drugs block hydrolysis of acetylcholine and are used for symptomatic improvement (pyridostigmine bromide)
- immunosuppressives
- plasmapheresis
- ventilator support may be needed during a crisis
Cause of MS
- autoimmune dz characterized by numbness, loss of muscle coordination an problems with vision, speech and bladder control
- immune system attacks myelin (serves as nerve insulator and helps in transmission of nerve signals)
S & S MS
weakness, numbness or unsteadiness in a limb; may progress to all limbs
- spastic paraparesis
- disequilibrium
- diplopia (MG too)
- urinary urgency or hesitancy
- optic atrophy
- nystagmus
labs and diagnostic MS
- slightly elevated protein in CSF
- elevated CSF IgG
- MRI or brain
Mngt MS
- no tx to prevent progression
- recovery from acute relapses hastened by steroids but extent of recovery not improved
- antispasmodics
- interferon therapy
- immunosuppressive therapy
- plasmapheresis
Guillain-Barre Syndrome. what is it (usually preceded by viral URI)
acute, rapidly progressive form of inflammatory polyneuropathy characterized by demyelination of peripheral nerves resulting in progressive symmetrical ascending paralysis
S/S of Guillain-Barre
- cranial nerve impairment-evidenced by difficulties in speech, swallowing and mastication
- reflexes are usually hypoactive or absent
- impairment of the muscles of respiration occur as the paralysis ascends
Labs and diagnostics of Guillain-Barre
- csf protein usually elevated (esp immunoglobulin G- IgG)
- CVC: see early leukocytosis with left shift
- LP, MRI, and CT may aid diagnosis
Management of Guillain-Barre
Treatment is supportive while myelin is regenerated
- symptoms begin to recede within two weeks with recovery in 2 years
- neuro consult
when should meningitis be considered?
in any pt with fever and neuro symptoms esp if there is hx of other infection
Causes of meningitis
- strep pneumoniae (seen in: meningitis, sinusistis, CAP, otitis)
- hemophilus influenzae
- neisseria meningitidis
