Neurology Flashcards
40yo male BIBA following seizure at home. He is febrile and wife says he was acting strange for 12h preceding the fit. He has no focal neurology, neck stiffness, photophobia or rashes and is otherwise stable. What single Tx do you give this patient?
Aciclovir. This is likely encephalitis, most likely caused by HSV. Do a LP for CSF and an MRI brain. CSF analysis will reveal a high protein, normal glucose, slightly high WBC (lymphocytes), positive HSV PCR
What are classic MRI findings of HSV encephalitis?
MRI should show inflammation involving the bilateral medial temporal lobe, insular cortex and cingulate gyrus
What are symptoms of a bulbar/ pseudobulbar palsy?
Dysphagia/ difficulty swallowing with dysarthria
What are some differential causes for a 3 month Hx of bulbar palsy/ LMN pattern of weakness in speech and swallowing apparatus?
Motor neuron disease (MND) and myasthenic gravis (MG). This may lead to proximal weakness
What pattern of neurological signs is usually observed in patients with MS?
Pseudobulbar or UMN pattern of weakness i.e. brisk jaw jerk and gag reflex, with slow spastic tongue movements (without wasting). Classically, in younger patients it presents with opthalmoplegia and ptosis.
What investigations would you carry out to confirm a diagnosis of myasthenia gravis?
A Tensilon test (cholinesterase Tx), which will show improvement of symptoms in MG. EMG studies, AChR antibodies may be used to confirm diagnosis. A CT upper thorax may be carried out to exclude thymomas.
What drugs make myasthenia gravis worse?
Myasthenic crisis may be triggered by certain drugs (e.g. cipro, propranolol, CCBs, Botox, lithium, verapamil) and neuromuscular blockers in anaesthesia.
What malignancy is a/w Lambert Eaton Myasthenic syndrome?
Small cell lung cancer, as LEMS is a paraneoplastic disorder - a pre-synaptic disorder of the NMJ with antibodies to voltage gated Ca channels.
What risk factors are a/w multiple sclerosis?
Family history, EBV infection, geographic latitude/ sunlight/ vitamin D/ smoking
What are the most common symptoms of MS?
- Optic nerve: optic neuritis
- Cerebellum: cerebellar syndrome (acute or chronic dysfunction)
- Brainstem: cranial nerve mono-neuropathies, INO, eye movement issues
- Spinal cord: transverse myelitis, incoordination and weakness, progressive paraparesis
What is the most common disease course of MS?
Relapsing-remitting disease (exacerbations followed by recovery)
What are clinical features of multiple sclerosis?
Visual - optic neuritis (partial or total unilateral visual loss over days, with pain behind eye and on movement), eye movement abnormalities
Motor and coordination - weakness LL >UL, UMN signs, ataxia, may present with clinical syndrome e.g. transverse myelitis
Sensory/ autonomic - pain paraesthesia and heat sensitivity, bladder/ bowel/ sexual dysfunction
Cognition - depression, fatigue, CI
What does heel-toe tandem walk indicate?
Cerebellar pathology - cf. DANISH - dysdiadokinesia, ataxia, nystagmus, intention tremor, slurred speech (dysarthria), heel-shin abnormality
What are causes of cerebellar signs?
Unilateral - MS, vascular, SOL
Bilateral - unilateral causes, inherited, metabolics, medications e.g. phenytoin
What causes intranuclear opthalmoplegia? i.e. inability to adduct affected side in lateral gaze/ conjugate gaze disorder
It is caused by demyelination of the MLF, which connects the CNVI (LR muscle) and CNIII (MR muscle).
