An 80-year-old man is investigated for progressive cognitive impairment.
Which one of the following features is most suggestive of Lewy body dementia?
Correct Answer C:
Lewy body dementia:
Lewy body dementia is an increasingly recognized cause of dementia, accounting for up to 20% of cases. The characteristic pathological feature is alpha-synuclein cytoplasmic inclusions (Lewy bodies) in the substantia nigra, para-limbic and neocortical areas.
The relationship between Parkinson's disease and Lewy body dementia is complicated, particularly as dementia is often seen in Parkinson's disease. Also, up to 40% of patients with Alzheimer's have Lewy bodies.
Neuroleptics should be avoided in Lewy body dementia as patients are extremely sensitive and may develop irreversible parkinsonism. Questions may give a history of a patient who has deteriorated following the introduction of an antipsychotic agent.
Features:
A 54-year-old man with small cell lung cancer complains of muscle weakness. Each one of the following are features of Lambert-Eaton syndrome, except:
Correct Answer D: In myasthenia gravis repeated muscle contractions lead to reduced muscle strength. The opposite is however classically seen in the related disorder Lambert-Eaton syndrome.
Lambert-Eaton syndrome:
Lambert-Eaton myasthenic syndrome is seen in association with small cell lung cancer, and to a lesser extent breast and ovarian cancer. It may also occur independently as an autoimmune disorder. Lambert-Eaton myasthenic syndrome is caused by an antibody directed against presynaptic voltage gated calcium channel in the peripheral nervous system.
EMG:
Management:
*in reality this is seen in only 50% of patients and following prolonged muscle use muscle strength will eventually decrease
**works by blocking potassium channel efflux in the nerve terminal so that the action potential duration is increased. Calcium channels can then be open for a longer time and allow greater acetylcholine release to the stimulate muscle at the end plate
A 54-year-old man is admitted to the Emergency Department with a left hemiplegia. His symptoms started around 5 hours ago and he has had no headache, visual disturbance or loss of consciousness. On examination a dense left hemiplegia is noted. Blood pressure is 120/78 mmHg, GCS is 15/15 and pupils are equal and reactive to light. An urgent CT scan is performed shortly after his arrival. This demonstrates no abnormality.
What is the most appropriate initial management?
Correct Answer E: Stroke thrombolysis - only consider if less than 3 hours and haemorrhage excluded.
This patient has had an ischaemic stroke. He is however outside the thrombolytic window and should therefore be treated with aspirin.
Stroke: management:
The Royal College of Physicians (RCP) published guidelines on the diagnosis and management of patients following a stroke in 2004. NICE also issued stroke guidelines in 2008, although they modified their guidance with respect to antiplatelet therapy in 2010.
Selected points relating to the management of acute stroke include:
Thrombolysis:
Thrombolysis should only be given if:
Secondary prevention:
NICE also published a technology appraisal in 2010 on the use of clopidogrel and dipyridamole.
Recommendations from NICE include:
With regards to carotid artery endarterectomy:
*the 2009 Controlling hypertension and hypotension immediately post-stroke (CHHIPS) trial may change thinking on this but guidelines have yet to change to reflect this
**SIGN recommend a window of 4.5 hours
***European Carotid Surgery Trialists' Collaborative Group
****North American Symptomatic Carotid Endarterectomy Trial
A 54-year-old man presents concerned about leg weakness. On examination he is noted to have increased tone in both legs, brisk reflexes and weakness in both lower limbs. Examination of his upper limbs is normal.
Which one of the following is least likely to produce these symptoms?
Correct Answer B: Amyloidosis is the least likely of the above options to result in a spastic paraparesis.
Spastic paraparesis:
Spastic paraparesis describes a upper motor neuron pattern of weakness in the lower limbs.
Causes:
Which one of the following is most likely to cause a bilateral facial nerve palsy?
Correct Answer D:
Facial nerve:
Supply - 'face, ear, taste, tear':
Causes of bilateral facial nerve palsy:
Causes of unilateral facial nerve palsy - as above plus:
LMN vs. UMN:
*may also cause an UMN palsy
Click to expand