Multiple Sclerosis and Other Demyelinating Disorders MCQs

Autoimmune inflammation and demyelination of CNS (brain and spinal cord) with subsequent axonal damage. Most often affects females aged 20-40 Symptoms may exacerbate with increased body temperature (eg, hot bath, exercise). Relapsing and remitting is most common clinical course. ↑IgG level and myelin basic protein in CSF. Oligoclonal bands aid in diagnosis. MRI is gold standard. Periventricular plaques A (areas of oligodendrocyte loss and reactive gliosis). Multiple white matter lesions disseminated in space and time.

Removal of adrenal gland leads to Addison's disease. Deficiency of mainly 3 hormones Due to mineralocorticoid deficiency: Hyponatremia, hyperkalemia, hypotension, small heart, nausea, vomiting Due to glucocorticoids deficiency: Hypoglycemia, fatigue, anorexia, skin pigmentation, weight loss, myalgia Due to adrenal androgen deficiency: Lack of energy, dry & itchy skin, loss of libido in women & loss of axillary & pubic hairs in women.

The use of suxamethonium is challenging in patients with neuromuscular disorders. Key points to remember include relative resistance to depolarisation in myasthenia gravis, often requiring an increased dosage, and the development of extrajunctional receptors in many of the myotonias, leading to extensive depolarisation and potentially fatal hyperkalemia with the use of depolarising neuromuscular blockade. In addition, there are disease-specific aspects of nondepolarizing neuromuscular blockade that should be noted,including the relative sensitivity in conditions such as Guillain-Barré syndrome. Hence dose reduction to 10-20% should be considered in addition to ongoing monitoring of blockade. Reference: Harrison 20 th 3188-3200

Chronic subdural haematoma is classically associated with fluctuating conscious level and cognitive function. Bilateral papilloedema may occur with raised intracranial pressure. Bilateral internuclear ophthalmoplegia is associated with multiple sclerosis and unilateral lesions of medial longitudinal fasciculus may occur with small brain stem infarcts. Unequal pupils are associated with rapid transtentorial coning in extradural haemorrhage leading to ipsilateral dilated pupil followed by bilateral fixed dilated pupils. Reference: Harrison's Principles of Internal Medicine, 21 st ed, Ch: 443, Pg: 3457

The white matter lesions suggest either multiple sclerosis or lymphoma. Infiltration with lymphocytes can be seen in Multiple Sclerosis too. In around 10% of patients with MS, OCB can be absent. However, the presence of constitutional symptoms makes the possibility of CNS lymphoma more likely. Reference: Harrison's Principles of Internal Medicine. 21 st Ed, Ch:90 Pg: 705

Ans. is 'a' i.e., No change Structural changes in the arterial walls are absent except late in the course, when intimal thickening can appear.

Fasciculation suggest lower motor neurone disease . It is seen usually in diseases affecting the anterior horn cells of spinal cord. It can also be seen in diseases of the nerve roots and peripheral nerves. However, it is absent in diseases of the muscles or neuromuscular junction. Cervical spondylosis is a disease which affects the spinal cord as well as the nerve roots. So it can cause fasciculations. Motor neurone disease is the prototype illness that presents with fasciculations. Spinal muscular atrophy is an LMN type of MND and hence can cause fascicuations. Multiple Sclerosis is a disease causing demyelination of the white matter of the central nervous system and hence presents with predominant UMN symptoms and can have sensory symptoms as well. Hence MS is the less likely cause. Reference: Harrison's Principles of Internal Medicine, 21 st ed, Ch: 447, Pg: 3411-3415

This patient who has a background history of an defective vision, now presents with symptoms suggestive of a spinal cord transection and MRI showing T2 hyperintense lesions. This is typical of Multiple Sclerosis. The acute episodes of Multiple Sclerosis is treated with steroids. Methylprednisolone 500-1000mg for 3-5 days, followed by a taper with oral steroids 60-80mg/day for two weeks. Reference : Harrison's Principles of Internal Medicine, 21 st ed, Ch: 444, Pg: 3468