Pathology of the Pituitary Flashcards
Where are the hormones of the posterior pituitary made?
Hypothalamus
What are the 3 cells of the anterior pituitary?
- Chromophobes
- Acidophils
- Basophils
What network makes up the anterior pituitary?
Reticulin Network
Hyperpituitarism
Over secretion of 1 or more hormones
What is the most common cause of hyperpituitarism?
Anterior Pituitary Adenoma
What are pituitary adenomas that produce hormones called?
Functional
What is the most common type of pituitary adenoma?
Prolactinoma
What are other common hormones secreted by pituitary adenomas?
- GH
- ACTH
What are some manifestations of pituitary adenoma?
- Headache
- Bitemporal Hemianopsia
What is the effect of GNAS1 mutation?
Leads to unchecked cellular proliferation - turning cell cycle on permanently.
What is the presentation of prolactinomas in females?
- Galactorrhea
- Amenorrhea
What is the presentation of prolactinomas in males?
- Impotence
- Infertility
What else can cause elevated prolactin?
- Decreased DOPA
- Drugs
What drugs are used to treat prolactinomas?
- Bromocriptine
- Cabergoline
What is the effect of GH-secretitng adenoma on prepubertal patients?
Gigantism
What is the effect of GH-secretitng adenoma on postpubertal patients?
Acromegaly
What are lab features of GH adenomas?
- Elevated GH
- Elevated IGF-1
- Lack of GH suppression by oral glucose
What is the treatment for GH adenomas?
- Surgery
- Somatostatin
- Octreotide
- Lantreotide
What can ACTH adenomas cause?
Cushing Disease
What is Cushing Syndrome?
Excess cortisol due to increased released from adrenals.
Distinct from Cushing Disease which is due to ACTH adenoma.
- Round face
- “buffolo hump”
- Osteopenia
- Hypertension
- Atherosclerosis
- Glucose intolerance
- Hyperlipidemia
- Increased susceptibly to Infections
- Depression
Cushing Syndrome
Nelson Syndrome
Adrenal glands removed for treatment of hypercortisolism due to Cushing Disease with an unknown presence of coritoctroph micro adenoma.
- No inhibitory effect of adrenal corticosteroids on pituitary adenoma so the adenoma will grow
Hypopituitarism
Deficiency of pituitary hormones
Pituitary Apoplexy
Acute hemorrhage into an adenoma
What is the most lethal hormone loss with loss of the pituitary?
ACTH
Sheehan Syndrome
Postpartum hemorrhage leads to necrosis of the anterior pituitary leading to lactation failure and lethal adrenal insufficiency
What are other causes of hypopituitarism?
- DIC
- Sickle Cell Disease
- Trauma
Empty Sella Syndrome
Enlarged sella turcica not filled entirely with pituitary tissue which leads to CSF leak and increases pressure around the pituitary and results in pituitary atrophy
Central Diabetes Insipidus
ADH deficiency - polyuria
SIADH
Excess ADH
Nephrogenic Diabetes Insipidus
Renal tubules do not respond to ADH
What are the causes of SIADH?
- Drugs
- CNS Injury
- Ectopic Secretion (Lung SCC)
- Idiopathic
Craniopharhygioma
– Benign tumor
– Arises from vestigial remnants of Rathke’s pouch
– Primarily suprasellar location
– Developmental Failure of Rathke’s pouch obliteration
– Lined by cuboidal epithelium with cilia and/or goblet cells
– Growth may compromise pituitary gland
Rathke Cleft Cysts
A 30‐year‐old woman, who has three healthy children, notes that she has had no menstrual periods for the past 6 months, but she is not pregnant and takes no medications. Within the past week, she has noted some milk production from her breasts. She has been bothered by headaches for the past 4 months. After nearly hitting a bus while changing lanes driving her vehicle, she is concerned with her vision. On physical examination she is afebrile and normotensive. Her lateral vision is reduced. Which of the following laboratory test findings is most likely to be present in this woman?
A. Increased serum cortisol B. Lack of growth hormone suppression C. Hyperprolactinemia D. Hyponatremia E. Abnormal glucose tolerance test F. Decreased serum TSH
C. Hyperprolactinemia
A 24‐year‐old presents with the onset of labor at 38 weeks gestation. As a consequence of placenta accreta she develops severe hemorrhage. She remains hypotensive for 4 hours and requires transfusion of 10 packed RBC units. Postpartum, she becomes unable to breast‐feed the infant. She does not have a resumption of normal menstrual cycles. She becomes more sluggish and tired. Laboratory findings include hyponatremia, hyperkalemia, and hypoglycemia. Which of the following pathologic lesions is she most likely to have had following delivery?
A. Bilateral adrenal hemorrhage B. Pituitary necrosis C. Metastatic choriocarcinoma D. Subacute thyroiditis E. Posterior pituitary adenoma
B. Pituitary necrosis
