Hypopituitarism
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Flashcards
Hypopituitarism
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Questions
USMLE® Step 1 style questions USMLE
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Reproduced from: Wikimedia Commons
Which of the following is the most likely diagnosis?
External References
First Aid
2024
2023
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2021
Bitemporal hemianopia p. 557
hypopituitarism as cause p. 343
Brain injury
hypopituitarism from p. 343
Corticosteroids
hypopituitarism p. 343
Craniopharyngiomas p. 542, 631
hypopituitarism with p. 349
Growth hormone (GH) p. 338, 362
for hypopituitarism p. 349
Hormone replacement therapy p. 674
for hypopituitarism p. 343
Hypopituitarism p. 343
Pituitary adenomas
hypopituitarism and p. 349
Radiation exposure
hypopituitarism p. 349
Transcript
Content Reviewers
With hypopituitarism, “hypo” means under and “pituitarism” refers to the pituitary gland which normally secretes various endocrine hormones.
So hypopituitarism is the underproduction of hormones released by the pituitary gland, and the symptoms depend on which hormones are actually undersecreted.
If all of the pituitary hormones are affected, it’s called panhypopituitarism.
The pituitary is a pea-sized gland, hanging by a stalk from the base of the brain.
It sits just behind the eyes near the optic chiasm, which is where the optic nerves cross and the gland rests in a very small depression of the skull known as the sella turcica.
The pituitary gland produces and secretes hormones when it receives signals from another part of the brain called the hypothalamus.
Together, they form the hypothalamic-pituitary axis which regulates the release of all the major endocrine hormones.
The pituitary itself has two distinct parts: the anterior pituitary and the posterior pituitary.
The anterior pituitary, which is the front of the pituitary gland, contains a few different types of cells, each of which secretes a different hormone.
The largest group of cells are the somatotropes which secrete growth hormone, which goes on to promote tissue and organ growth.
The second largest cell group are the corticotrophs which secrete adrenocorticotropic hormone, or ACTH, which stimulates the adrenal glands to secrete cortisol, a hormone that controls the stress response, blood pressure, and metabolic regulation.
A smaller cell group are the lactotrophs which secrete prolactin.
Prolactin stimulates breast milk production, and also inhibits ovulation, which is when an egg cell is released from the ovary, and inhibits spermatogenesis, which is the development of sperm cells.
Summary
Hypopituitarism refers to the underproduction of any of the hormones released by the pituitary gland. If all of the pituitary hormones are underproduced, it's called panhypopituitarism. Hypopituitarism can be caused by tumors, pituitary hemorrhage or infarction, or accidental damage during radiation or surgery. Symptoms vary greatly depending on which hormones are impacted. Common symptoms include fatigue, weight gain, depression, low blood pressure, and problems with sexual function.
Sources
- "Robbins Basic Pathology" Elsevier (2017)
- "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
- "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
- "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
- "Harrison's Endocrinology, 4E" McGraw-Hill Education / Medical (2016)
- "Management of Hypopituitarism" Journal of Clinical Medicine (2019)
- "Hypopituitarism After Traumatic Brain Injury" Cureus (2019)