Inflammation and infection Flashcards
What is multiple sclerosis?
Autoimmune demyelination of the central nervous system
Onset 20-40yrs
Predominantly affects the white matter
Has multiple relapses
Doesn’t cause death directly, more due to immobility effects
What are some symptoms of Multiple sclerosis?
- Sensory loss (early)
- Spinal cord symptoms:
Motor: Muscle cramping secondary to spasticity
Autonomic: Bladder, bowel, and sexual dysfunction - Cerebellar symptoms - Charcot triad of dysarthria (scanning speech), nystagmus, and intention tremor
- Optic neuritis
- Trigeminal neuralgia - Bilateral facial weakness or trigeminal neuralgia
- Facial myokymia (irregular twitching of the facial muscles) - May also be a presenting symptom
- Eye symptoms - Including diplopia on lateral gaze; these occur in 33% of patients
- Heat intolerance
- Constitutional symptoms - especially fatigue (which occurs in 70% of cases) and dizziness; fatigue must be differentiated from depression (which may, however, coexist), lack of sleep, and exertional exhaustion due to disability
- Pain
- Cognitive difficulties
- Depression
- Euphoria - Less common than - Depression
- Bipolar disorder or frank dementia
What is the difference between grey and white matter?
White matter is the connections for the grey matter
How is MS diagnosed?
Prove changes with MRI and take CSF that shows oligoclonal bands and bloods for systemic inflammation
Because MS is and autoimmune disease of the CNS
How is MS managed?
Acute relapse: steroids and immunomodulation (disease modifying treatment)
Treat symptoms
What is Baclofen used for in MS?
First line for spasticity
What is Guillain-Barré
syndrome?
Autoimmune demyelination of peripheral nerves
Develops 2-4 weeks after a respiratory or GI infection
Can cause death because is affects swallowing and breathing
Which cells contain the myelin in the CNS compared to the PNS?
CNS: Oligodendrocytes
PNS: Schwann cells
What are some symptoms of Guillain-Barré syndrome?
Symmetrical symptoms
Paraesthesia
Dysphagia
Weakness ascending from legs up
Autonomic dysfunction
Better outcome if diagnosed early
How is Guillain-Barré syndrome diagnosed?
Prove disease in PNS that is autoimmune
Nerve conduction study equivalent to MRI scan in MRI
High protein in CSF (cauda equina in PNS)
History + examination
Eg. absent reflexes (unlikely to be GBS if present), flaccid paralysis, reduced power and sensation
(Everything is reduced)
How is Guillain-Barré syndrome treated?
Steroid don’t work
DMARDS are too slow
Give IV immunoglobulin to destroy the bad antibodies or do plasma exchange
Treatment needs to be rapid and getting rid of the bad antibodies is key
What is Giant cell arteritis?
Autoimmune
Causes headaches, scalp tenderness, jaw pain and vision problem
What is myasthenia gravis?
A neuromuscular junction disease where antibodies block transmission from motor neurone to muscle
- Causes paralysis and weakness
The more you do, the weaker you get. So worse symptoms later in the day
Doesn’t cause sensory issues
How is Myasthenia gravis diagnosed?
Look for autoantibodies
What is Encephalitis?
Viral infection
Most commonly by Herpes simplex
Altered mental state
+ fever =CSF
+ Seizures =MRI
+ Focal signs =EEG
Why is it important to diagnose encephalitis early?
It progresses quickly
The earlier the treatment, the better the outcome
How do you diagnose Herpes simplex encephalitis?
Do a PCR of herpes
How is encephalitis treated?
Treat the cause
Herpes: IV acyclovir
What is Bell’s palsy?
1 sided facial weakness
Affects the facial nerve (CN7)
Eye-opening is spared because those nerves are not the facial nerve
Treat with steroids +/- acyclovir
What is Uhthoff’s phenomenon?
Worsening of MS neurological symptoms on exercise/in warm environments (e.g. in a bath)
Lasts <24hours
What is Lhermitte’s phenomenon?
Lightning-shock pain down the spine on flexion of the neck secondary to cervical cord plaque formation
What are the symptoms of the CNS being affected by MS?
Motor:
Loss of power
Spasticity
Sensory:
Increasing sensitivity to pain
Tingling
Burning
Paraesthesia
Cerebellar:
Loss of balance
Diplopia
Dysarthria
Tremor
Fatigue
Depression/labile mood
What are the symptoms of the ophthalmic system being affected by MS?
Nystagmus
Optic neuritis (pain on movement, visual field defect, loss of colour vision – particularly red)
Diplopia – internuclear ophthalmoplegia (INO)
What are the symptoms of the Otolaryngeal system being affected by MS?
Dysphagia
Slurring/stuttering speech
What are the symptoms of the muscular system being affected by MS?
Weakness
Cramping
Spasm/contractures
What are the symptoms of the urinary system being affected by MS?
Urinary frequency
Incontinence
Retention
What are the symptoms of the GI system being affected by MS?
Constipation or diarrhoea
Which areas are important to cover in a history of MS?
- Past medical history (such as any history of focal neurologic deficit, or other autoimmune diseases)
- Family history of MS/other autoimmune diseases
- Smoking status
- Diet
- Impact on activities of daily living
- Driving status
- Falls risk assessment
What are the examination findings of MS?
CN1: Optic neuritis: fundoscopy may reveal a blurry optic disc, Nystagmus
CN5: Facial paraesthesia
CN7: Forehead sparing facial weakness
CN8: Loss of balance/hearing
CN9/10/12: Loss of motor function of tongue/ pharynx causing speech and swallowing issues
CN11: LOF of sternocleidomastoid and trapezius causing neck weakness and hypotonia
What are some lab tests done for MS?
Done to rule out other causes
- FBC (infection)
- CRP (marker of inflammatory process infective/autoimmune)
- LFT: ( rule out hepatic pathology)
- U&E’s: (electrolyte disturbances)
- Ca2+ and angiotensin converting enzyme: rule out sarcoidosis
- Thyroid function
- B12: rule out B12 peripheral neuropathy
- HIV serology
What is the McDonald criteria?
The clinical, radiological and biochemical findings which must be met to make a diagnosis of MS
What are the 4 subtypes of GBS?
- Acute inflammatory demyelinating polyneuropathy (AIDP): most common in western Europe and north America. Primarily affecting the myelin sheath of affected nerves
- Acute motor axonal neuropathy (AMAN): More common in Asia. Primarily damages the axons of motor neurons specifically. This results in a purely motor presentation.
- Acute motor sensory axonal neuropathy (AMSAN): affecting motor and sensory neurons. Associated with a poorer rate of recovery.
- Miller-Fisher syndrome: a form of GBS defined by antibodies to the GQIb ganglioside, typically associated with a triad of ophthalmoplegia, ataxia, and areflexia. No treatment is required
