Endo Pathology Flashcards
Pituitary adenoma
It is benign tumor of the anterior pituitary gland
Classify pituitary adenomas based on function
- Functional
- Non-functional
Functional pituitary adenomas include:
Prolactinoma
GH cell adenoma
ACTH cell adenoma
Prolactinoma features
It’s features are associated with excess production of prolactin hormone
In females:
1. Galactorrhea
2. Amenorrhea due to inhibition of GnRH by prolactin therefore inhibiting the release of FSH and LH
In males:
1. Decreased libido and headaches
What is the most common type of pituitary adenoma
Prolactinoma
Treatment of prolactinoma
- Dopamine agonists such as Bromocriptine, cabergoline help reduce tumor size
- Surgery for larger lesions
Cells that produce prolactin are called
Lactotrophs
GH cell adenoma effects on Children and adults
In Children:
1. Gigantism: due to linear growth of bones
In Adults:
1. Acromegaly:
a) Increased size of hands, feet, jaw
b) Increased size of visceral organs such as the heart leading to cardiac failure
c) Enlarged tongue
- Secondary diabetes mellitus
How does GH cell adenoma cause secondary diabetes ?
Increased GH hormone induces gluconeogenesis from the liver also, it has an anti-insulin effect where it prevents uptake of glucose by cells.
All this helps to make glucose available for energy in promoting growth
How is GH cell adenoma diagnosed
By testing for
1. Elevated GH levels and Insulin growth factor 1 levels ( IGF-1)
- No decreasing effect on GH levels on administration of oral glucose
Treatment of GH cell adenoma
- Octreotide - somatostatin analogue
- Surgery
ACTH cell adenomas lead to?
Cushing’s syndrome
Nonfunctional pituitary adenomas present as __ which leads to:
A mass
Which leads to
1. Bitemporal hemianopsia due to compression of optic chiasm
2. Hypopituitarism due to compression of normal pituitary tissue
3. Headaches
Hypopituitarism
Decreased production of pituitary hormones by the anterior pituitary
Symptoms of Hypopituitarism occur when how much percentage of pituitary parenchyma is lost?
More than 75%
What are the causes of hypopituitarism?
- Pituitary adenoma in adults
- Craniopharyngioma in children
- Sheehan syndrome
- Empty sella syndrome
How does pituitary adenoma and Craniopharyngioma cause hypopituitarism ?
Due to the following reasons including:
1. Mass effect therefore compressing normal pituitary
2. Pituitary apoplexy ( bleeding into pituitary adenoma) cause enalargement and compression
How does sheehan syndrome cause hypopituitarism
In Pregnancy, there is increased hormones demand there leading to hypertrophy of pituitary gland but the blood supply remains the same
In case of bleeding during parturition, it may lead to infarction of pituitary gland
What are the clinical presentations of sheehan syndrome
- Poor lactation
- Loss of pubic hair
- Fatigue
How does Empty sella syndrome cause hypopituitarism
Empty sella syndrome may be primary or secondary
In primary, there is herniation of arachnoid and csf into sella turcica therefore compressing and destroying the pituitary gland
In secondary there is destruction of pituitary gland either by surgery, trauma etc
What is the clinical presentation of empty sella syndrome
Absent pituitary on imaging
Pathologies of the posterior pituitary
- Central diabetes insipidus
- Nephrogenic diabetes insipidus
- Syndrome of Inappropriate ADH secretions ( SIADH)
Central diabetes insipidus
It is a disease caused by ADH insufficiency
Causes of Central diabetes insipidus
Hypothalamus or posterior pituitary pathologies such as trauma, surgery, tumor, infections etc
