Endocrine Pathology

Front 1

What are the hormones of the posterior pituitary?

Back 1

ADH (vasopressin) and oxytocin

Front 2

Pituitary adenoma:
- Most common cause of hyperpituitarism.
- Classified based on the hormones that are produced.
- PRL, GH, and ACTH are the most common.
- Microadenomas are found in 25% of autopsies.

Back 2

What is this mass?

Front 3

What are the three most common mutations seen in pituitary adenomas?

Back 3

- G protein mutations: commonly secrete somatostatin and cortisol, but infrequently anything else.
- Mutation on chromesome 11q3 causes multiple endocrine neoplasia (MEN-1), but only causes 3% of adenomas.
- RAS and MYC are seen in the most aggressive tumors.

Front 4

Adenomas that are this large infrequently have a hormone secretion.

Back 4

What hormone does this pituitary adenoma secrete?

Front 5

What are the major clinical characterisitics of a prolactinoma?

Back 5

- 30% of functioning pituitary adenomas (the most common type).
- More common in women.
- Presents with a classic triad: amenorrhea, galactorrhea, and infertility.
- 25% of women with amenorrhea present with prolactinoma.
- Diagnosis: PRL levels of less than 20 ng/Dl will exclude.
- Treatment: Bromocriptine a dopamine recetor agonist.

Front 6

What are the major clinical charactersistics of a somatotroph cell adenoma?

Back 6

- Second most common functioning pituitary adenoma.
- Tumors can be basophilic or chromatophobic.
- Symptoms: If before full growth, giagantism, if after, acromegaly.
- Diagnosis: Elevated GH and IGF-1, GH release not supprsed by the glucose load, and imaging studies.
Treatment: Surgery.

Front 7

What are the major clinical characterisitics of a corticotroph cell adenoma?

Back 7

- Tumors are often basophilic, but sometimes chromophobic.
- Exccess ACTH production leads to hypercortisolism (Cushing disease).
- Nelson syndrome is a large adenoma that occurs after an adrenalectomy.

Front 8

What are the major clinical characterisitics of a gonadotroph?

Back 8

- Difficult to diagnose because it secretes variably and without clinical effect.
- Middle aged patients may experience headaches and visual disturbances.

Front 9

What is the most rare pituitary adenoma?

Back 9

Thyrotrophs only make up 1% of the pituitary adenomas.

Front 10

How much of the pituitary must be lost before symptoms emerge?

Back 10

75%

Front 11

What are the common causes of hypopituitarism?

Back 11

- Mass lesions
- Surgery in the area
- Pituitary apoplexy (hemorrhage into an adenoma)
- Ischemic necrosis of pituitary
- Sheehan syndrome: Post-partum necrosis of the pituitary
- Empty sella syndrome
- Genetic defects: Rare
- Lesions of the hypothalamus

Front 12

What are the subtypes of diabetes insipidus?

Back 12

- Too little ADH is secreted, or the ADH that is secreted is ineffectual.
- Neurogenic: Too little is secreted.
- Nephrogenic: The kidney fails to respond.
- Primary polydipsia: Abnormal thirst causes too much water intake.
- Gestational: Increased metablism of vasopressin causes deficiency.
- Symptoms: Polyuria, polydipsia, hypernatrimia, enuresis.

Front 13

What are the causes of diabetes insupidus?

Back 13

Familal mutations, tumors, pituitary surgery.

Front 14

What are two causes of the syndrome of inappropriate ADH syndrome?

Back 14

- Abnormal regulation of ADH secretion with high levels of ADH.
- Ectopic secretion of ADH by a malignant tumor (small cell carcinoma most commonly).

Front 15

What are the major clinical characteristics of syndrome of inappropriate ADH?

Back 15

- Weakness and general deteriation.
- Confusion and seizures.
- Nausea and vomiting.
- Hyponatremia is the only abnormal lab value.

Front 16

What are the characterisitics of a carniopharyngioma?

Back 16

- Derived from the remnants of Rathke's pouch.
- Slow growing
- Occurs in the hypothalamic region and cause growth defect, visual disturbance, and diabetes insipidus.
- Bimodal age distrubance.

Front 17

What is the most common cause of hypopituitarism in children?

Back 17

Craniopharyngoma

Front 18

Craniopharyngoma:
- Remanants of Rathke's pouch
- Characterisitic cyst formation with epithelial cells present
- Difficult to eradicate, but good prognosis.

Back 18

What is this pathology?

Front 19

What locations are common for ectopic thyroid tissue and which area is the most common?

Back 19

Ectopic tissue can be found anywhere along the thyroglossal duct, but is most usually found in the lingual region.

Front 20

What is the most common congenital throid anomaly?

Back 20

Thyroid cysts:
- Remnant of the thyroglossal duct.
- Does not cause any pathology.

Front 21

These are thyroid cysts and they are not associated with any pathology.

Back 21

What are the complications from the pathology viewed here?

Front 22

What is a diffuse (simple/colloid) nontoxic goiter?

Back 22

A form of goiter that involves the entire thyroid gland and cuases it to become non-functional.

Front 23

What is a multinodular goiter?

Back 23

Recurrent episodes of hyperplasia because of a diffuse goiter results in formation of a multinodular goiter. This is also due to varying sensitivity of the follicular epithelium.

Front 24

What is a toxic goiter?

Back 24

Describes a goiter that produces thyroid hormone.

Front 25

What is thyroiditis?

Back 25

Inflammation of the thyroid gland caused by many issues.

Front 26

This is a nodular goiter:
- Common worldwide because of iodine defciencies in developing nations
- Uneven enlargement of the thyroid gland
- Possible that nodules are hot

Back 26

What is this pathology?

Front 27

What is thyrotoxicosis?

Back 27

The clinical finding of an increasing metabolic state because of incrasing circulating levels of T3 and T4.

Front 28

What is hyperthyroidism?

Back 28

Similar to thyrotoxicosis, but causes thyroid dysfunction secondary to a primary thyroid disorder.

Front 29

What is subclinical hyperthyroidism?

Back 29

Low TSH associated with normal levels of T3 and T4.

Front 30

What is thyroid ophthalmopathy (exopthalmos)?

Back 30

This is an accumulation of loose connective tissue in the posterior orbit causing the prominent protuberence of the eyes in Grave's disease.

Front 31

What is a thyroid storm?

Back 31

Abrubt onset of severe thyrotoxicosis.

Front 32

What are the major clinical characterisitics of thyrotoxicosis?

Back 32

- Increased BMR.
- Cardiac symptoms (tachycardia)
- Weight loss
- Heat intolerance
- Nervousnous
- Ten times more common in women.
- Goiter more likely in younger patients.

Front 33

What are four basic causes of sustained thyrotoxicosis?

Back 33

- Primary: Overactivity of the thyroid, by far the most common.
- Secondary: Excessive thyroid stimulating hormone.
- Tertiary: Caused by hypothalamic disorders.
- Exogenous: Caused by taking thyroid hormones.

Front 34

What are the causes of transient thyrotoxicosis?

Back 34

(1.) Subacute granulomatous thyroidosis
(2.) Subacute lymphocytic thyroiditis
(3.) Hashimoto thyroiditis

Front 35

What are causes of primary hyperthyroidism?

Back 35

(1.) Graves disease
(2.) Toxic multinodular goiter
(3.) Toxic adenoma
(4.) Drug-induced goiter
(5.) Amiodarone: Antiarrythmic agent that has hyperthyroidism as a side effect.
(6.) Iodides: Used in prescription drugs.
(7.) Lithium induced hypothyroidism onccurs in depression patients.

Front 36

What are the causes of secondary hyperthyroidism?

Back 36

- Autonomous TSH secerting pituitary hormone.
- Ectopic TSH production is associated with small cell carcinoma.
- Agonist effect of HCG, a complication of molar pregnancy.
- Mutation of pituitary hormone beta receptor: resistance of thyroid hormone to shut down TSH secretion.

Front 37

What are the causes tertiary hyperthyroidism?

Back 37

- Hypothalamic induced TSH via TRH (rare).

Front 38

What are two causes of exogenous hyperthyroidism?

Back 38

- Iatrogenic: Excessive administration of thyroxine by physicians.
- Factitious thyrotoxicosis: result of patient self administering excessive doses of thyrotoxicosis.