QuestionSBA
QuestionChoice
No, this is not the single best answer, as it is the MSH specifically resulting in the hyperpigmentation within the skin.
10007828
d
Decreased cortisol production so there is increased POMC (pro-opiomelanocortin) production
QuestionChoice
This patient is exhibiting symptoms of Addison's disease. This is characterised by adrenal insufficiency resulting in reduced cortisol production, which in turn results in reduced negative feedback on the anterior hypothalamus so there are elevated levels of ACTH.
10007826
b
Reduced ACTH production
QuestionChoice
This patient is exhibiting symptoms of Addison's disease. This is characterised by adrenal insufficiency resulting in reduced cortisol production, which in turn results in reduced negative feedback on the anterior hypothalamus so there are elevated levels of ACTH.
10007827
c
Reduced ACTH production so there is reduced POMC (pro-opiomelanocortin) and MSH (melanocyte-stimulating hormone) production
QuestionChoice
No, this is not the single best answer, as there is increased POMC and MSH secretion that results from the increase in ACTH. It is the increased production of MSH which directly leads to hyperpigmentation of the skin.
10007829
e
Decreased cortisol production so there is increased ACTH production
QuestionChoice
This patient is exhibiting symptoms of Addison's disease. This is characterised by adrenal insufficiency resulting in reduced cortisol production, which in turn results in reduced negative feedback on the anterior hypothalamus so there are elevated levels of ACTH. POMC (pro-opiomelanocortin) is required for the production of ACTH and MSH. So if there is increased ACTH production, there is an increased need to produce POMC. MSH is also a breakdown product of POMC, hence there will be increased MSH levels leading to increased stimulation of melanin by melanocytes within the epidermis.
10007825
a
Increased ACTH production causing increased POMC (pro-opiomelanocortin) and MSH (melanocyte-stimulating hormone) production
Concept
Chapter
2693
3835
Adrenal insufficiency and Addison's Disease
Topic
133
Endocrinology
14112
A 54-year-old woman presents to the GP with lethargy and recent anorexia. She also reports that she has been feeling quite dizzy recently. On examination, she has patches of hyperpigmentation present on her palmar creases and gums.

After measuring her 9am cortisol and ACTH (adrenocorticotropic hormone) level, a diagnosis of addison's disease is suspected.

Which of the following describes the pathophysiology behind this patient's hyperpigmentation symptoms?
a