Which is a chronic, progressive and degenerative disorder that occurs due to the destruction of myelin sheath?

DSSSB October 2024

Medical & Surgical Nursing

Easy

Appeared in: DSSSB October 2024

Explanation

Multiple sclerosis (MS) is a chronic, progressive autoimmune disease that specifically targets the central nervous system (CNS).
The core pathophysiology of MS is the immune-mediated destruction of the myelin sheath, the protective covering that insulates nerve fibers.
This process, known as demyelination, disrupts the transmission of nerve impulses, leading to the wide array of motor, sensory, and cognitive symptoms characteristic of the disease.
The course of MS is typically relapsing-remitting, meaning periods of acute attacks (relapses) are followed by periods of recovery (remissions), with disability accumulating over time.

Option A: Myasthenia gravis is an autoimmune disorder, but it affects the neuromuscular junction by destroying acetylcholine receptors, leading to muscle weakness. It does not involve demyelination of the CNS.
Option B: Parkinson's disease is a neurodegenerative disorder characterized by the loss of dopamine-producing neurons in the substantia nigra. Its primary pathology is not demyelination.
Option D: Guillain-Barré syndrome (GBS) involves demyelination, but it is an acute, not chronic, condition. Furthermore, it affects the peripheral nervous system (PNS), not the central nervous system (CNS).

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pathophysiology of chronic neurodegenerative disorders as background academic context rather than a clinical decision trigger.
Nurses play a vital role in managing MS by helping patients adapt to a chronic, unpredictable illness. This includes patient education on trigger avoidance (like heat), medication adherence, and managing symptoms like fatigue and spasticity.
A key nursing priority is promoting safety and preventing complications from immobility, such as pressure ulcers and contractures, as the disease progresses.
What if? If the patient presented with acute, rapidly ascending paralysis starting in the legs after a recent viral illness, the most likely diagnosis would shift to Guillain-Barré syndrome. This would require immediate hospitalization and close monitoring of respiratory function, as GBS can lead to respiratory failure.

How to Approach the Question

First, dissect the question stem to identify the key defining characteristics: 1) chronic, 2) progressive, 3) degenerative, and 4) destruction of the myelin sheath.
Evaluate each option against these four criteria.
Eliminate Parkinson's disease and Myasthenia gravis, as their primary pathology is not demyelination.
You are left with two demyelinating diseases: Multiple sclerosis and Guillain-Barré syndrome.
Differentiate between these two by focusing on the terms 'chronic' and 'progressive'. MS is a chronic, progressive disease of the CNS. GBS is an acute disease of the PNS.
Based on this analysis, Multiple sclerosis is the only option that fits all the criteria in the question.

Concept Tested & Keywords

Concept Tested: Pathophysiology of chronic neurodegenerative disorders
Stem keywords: chronic, progressive, degenerative disorder, destruction of myelin sheath
Lead-in keywords: Which is

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