Short Quiz on Multiple sclerosis
Instruction
2. There is 1 Mark for each correct Answer
Ampicillin
In multiple sclerosis, the MR imaging will show lesions in which of the following structure?
MR imaging in multiple sclerosis will show lesions in white matter with a periventricular predominance.
In Multiple sclerosis, demyelinating plaques occur in the periventricular regions, corpus callosum, brainstem, and cerebellum.
Plaques are more periventricular, oval in shape, have irregular margins, and are oriented perpendicular to ventricles.
Demyelination is the major feature of Multiple Sclerosis. Which of the following cells forms myelin in the central nervous system?
The myelin sheath is formed by oligodendrocytes in CNS and by Schwann cells in the peripheral nervous system (PNS).
The gaps formed between myelin sheath cells along the axons are called nodes of Ranvier.
Since the lipid structure of myelin serves as a good insulator, the myelin sheaths increase the rate of propagation and efficacy of transmission of the impulse along the axon.
The electrical impulse jumps from one node to the next at the rate as fast as 120 m/s. This rapid type of conduction is called saltatory conduction. Demyelination can occur early in life as consequence of congenital metabolic disorders. Demyelination later in life can be repaired with glia, which explains the frequent exacerbations and remissions in MS. It is believed that in MS, multiple mechanisms of immune injury of myelin coexist: cytokine-mediated injury of oligodendrocytes and myelin, digestion of surface myelin antigens by macrophages, complement-mediated injury, and direct injury by CD4+ and CD8+ T cells. This type of injury causes the loss of saltatory conduction in nerve fibers. The exposed axon is susceptible to further injury, resulting in irreversible axonal damage.
Histocompatibility antigens are glycoproteins that are expressed at the surface of all vertebrate cells.
Human HLA antigens are present on the surface of all nucleated cells.
Major histocompatibility antigens are major antigens responsible for tissue recognition, and stimulate the acute, rapid type of graft rejection.
Each person has unique HLA antigens.
The presence of some HLA antigens have been correlated with the certain autoimmune diseases.
Susceptibility to MS is linked to the HLA-DR2 haplotype.
Which of the following is the only drug is found to be beneficial in halting the progression on EDSS of multiple sclerosis:
Ans is ‘c’ i.e. Natalizumab
* EDSS (Expanded disability status scale) is a method of quantifying disability in multiple sclerosis.
* EDSS steps 1.0 to 4.5 refer to people with MS who are fully ambulatory. EDSS steps 5.0 to 9.5 are defined by the impairment in amubulation. EDSS 10 is defined as death due to MS.
* Natalizumab silences disease activity and rapidly improves disability status and walking performance, possibly through delayed relapse recovery in patients with RRMS who had shown a high level of disease activity under other disease modifying drugs for multiple sclerosis.
Ans.A. Optic Neuritis
Optic Neuritis is the most frequent initial presenting feature of MS amongst the options provided.
The most common earliest presenting features of multiple sclerosis are transient sensory defects followed by visual disturbances due to optic neuritis.
Initial Symptoms of MS
|
Symptom |
Percent of Cases |
Symptom |
Percent of Cases |
|
Sensory loss |
37 |
Lhermitte’s |
3 |
|
Optic neuritis |
36 |
Pain |
3 |
|
Weakness |
35 |
Dementia |
2 |
|
Paresthesias |
24 |
Visual loss |
2 |
|
Diplopia |
15 |
Facial palsy |
1 |
|
Ataxia |
11 |
Impotence |
1 |
|
Vertigo |
6 |
Myokymia |
1 |
|
Paroxysmal attacks |
4 |
Epilepsy |
1 |
|
Bladder |
4 |
Falling |
1 |
Answer: c. Absence of oligoclonal bands (Ref Harrison I9/e p2656. 18/e p3372)
Oligoclonal bands are variable; but when bands are present, a diagnosis of MS is more likely, thus absence of oligoclonal bands suggests a less likely progression to MS.
Answer- A. Relapsing remitting type
Repapsing-remitting multiple sclerosis (RRMS)
This is the most common form of multiple sclerosis.
About 85% of people with M.S. are initially diagnosed with relapsing-remitting multiple sclerosis.
Investigation of choice for multiple sclerosis
Answer- B. MRI
MRI is the investigation of choice for demyelinating disorder, e.g. multiple sclerosis.
In multiple sclerosis, slow conduction of motor and the sensory pathways is due to?
Ans: B. Loss of the myelin sheath
-
Multiple sclerosis (MS) is an autoimmune disorder in which the immune system attacks and damages the myelin sheath, which is the protective covering around nerve fibers in the central nervous system. It increases the speed at which these signals are conducted by allowing the electrical impulses to jump between gaps in the myelin, known as nodes of Ranvier, rather than moving continuously along the nerve fiber.
When the myelin sheath is damaged or lost, as in MS, this rapid, saltatory conduction is disrupted. As a result, electrical impulses are slowed down or may not be conducted at all, leading to the various neurological symptoms characteristic of MS.
Answer C) Cervical spinal cord
Explanation:
Cervical Spinal Cord Section
-
The nerves exiting the vertebrae in the neck area or cervical segments are referred to as C1 through C8.
-
These nerve control signals to the neck, arms, hands, and internal organs. Injuries to these areas result in tetraplegia(also known as quadriplegia)
-
Injuries at the cervical level can distort where your body is positioned in space (proprioception.)
-
An injury above the C3 level may require a ventilator for breathing.
Thoracic Spinal Cord Section
-
Nerves in the thoracic or rib cage area (T1 through T12) relay signals to the torso and some parts of the arms.
-
Individuals with injuries from T1 to T8 usually affect control of the upper torso, limiting trunk movement and sensation as the result of a lack of abdominal muscle control. This can affect balance as well as proprioception (where your body is in space).
-
Those individuals with lower thoracic injuries (T9 through T12) have trunk control and some abdominal muscle control.
