Question

The following case relates to the next two questions. A 46-year-old man finds that, over a period of time, he has progressive bilateral weakness of both upper and lower limbs beginning with the muscles of the hands. However, testing reveals that sensory functions appear normal. Eventually, this individual is found to have wasting of muscles, fasciculations, and evidence of upper motor neuron (UMN) dysfunction together with an increase in tendon reflexes. After a few additional months, the patient develops facial weakness and an inability to swallow (dysphagia). Further analysis reveals abnormalities in the electromyegram (EMG) of the upper and lower extremities, denervation atrophy. However, the cerebrospinal fluid (CSF) remains normal.

Question 1. This patient is most likely suffering from

1. MS
2. Amyotrophic lateral sclerosis (ALS)
3. Poliomyelitis
4. Myasthenia gravis
5. Cerebral cortical stroke

Question 2. The neuronal regions affected include

1. Dorsal horns of the spinal cord
2. Lateral columns of the spinal cord
3. Ventral horns of the spinal cord
4. Dorsal columns and ventral horns of the spinal cord
5. Ventral horns and lateral horns of the spinal cord

In addition,

1. you should provide the reason of why you made your choice.
2. try to explain the cause of denervation muscle atrophy.

Answer 1

Answer 1:

The correct option is “B. Amyotrophic lateral sclerosis (ALS)”

ALS is a condition or disease which cause progressive neurodegenerative disease affecting the nerve cells located in brain and spinal cord. It is also common type as MSD (Motor Sensory Disorder) where there is no nourishment of muscles. This causes progressive inability in voluntary muscle action. Like facial muscles and limb muscles inaction.

Answer 2:

The correct option is “B. Lateral columns of the spinal cord”

In ALS (Amyotrophic lateral sclerosis), “lateral” specifies the portion of spinal cord where the nerve cells controlling muscle action are located. Thus, lateral columns of the spinal cord is the neuronal region which gets affected by ALS.

ALS is the most common type of denervation muscle atrophy and is caused due to nourishment loss of muscles (A – myo – tropic i.e No – Muscle - Nourishment). Here the lateral column of spinal cord is affected where the neurons controlling voluntary muscles actions are located. This causes the denervation of lower motor neuron causing loss of myofilaments.

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