Endocrine Associations_PATHOMA Flashcards
What is the #1 cause of ENDOGENOUS CUSHING SYNDROME?
CUSHING DISEASE - ACTH-secreting pituitary adenoma
Which causes of CUSHING SYNDROME will there be bilateral adrenal hyperplasia? (BAH)
- CUSHING DISEASE - ACTH Secreting pituitary adenoma
2. PARANEOPLASTIC ACTH SECRETION (Small cell lung carcinoma, bronchial carcinoids)
DECREASED ACTH (Corticotropin). What are the only 2 possible causes of CUSHING SYNDROME?
ACTH-independent CUSHING SYNDROME: Exogenous corticosteroids + adrenal adenoma
Excess cortisol is NOT dependent on a high level of ACTH
INCREASED ACTH (CORTICOTROPIN). What are the only 2 possible causes of CUSHING SYNDROME?
ACTH-DEPENDENT CAUSES: Cushing Disease (ACTH-secreting pituitary adenoma) + Ectopic paraneoplastic ACTH secretion by small cell lung carcinoma
Bilateral atrophy of adrenal glands. What cause of Cushing Syndrome am I?
EXOGENOUS CORTICOSTEROIDS - MORE COMMON
Non-functioning adenoma of anterior pituitary
UNILATERAL ATROPHY, UNILATERAL HYPERTROPHY of adrenal glands. What cause of Cushing Sydnrome am I?
Adrenal Adenoma/hyperplasia/carcinoma
What is the most common type of CONGENITAL ADRENAL HYPERPLASIA?
21-beta hydroxylase deficiency
Which type of CAH do you get HYPOTENSION + HYPERKALEMIA?
Which type of CAH do you get HYPERTENSION + HYPOKALEMIA?
HYPOTENSION + HYPERKALEMIA - 21-beta hydroxylase deficiency
HTN + HYPOKALEMIA - 11OH-ase and 17-OHase deficiency
Why do you get HTN with 11-OHase deficiency?
Bec you still get 11-DEOXYCORTISONE (weak mineralocorticoid) production -> HTN
What is common in all types of CAH?
LOW CORTISOL -> Loss of negative feedback -> HIGH ACTH -> Bilateral adrenal hyperplasia
Which types of CAH is there HIGH 17-OH progesterone and which type(s) has LOW 17-OH progesterone?
HIGH - 21-OHase, 11-OHase deficiency (shunting towards androgen pathway)
LOW - 17-OHase deficiency (shunting AWAY from androgen/GC pathway, and only towards MC pathway)
What is the most common cause of PRIMARY HYPERALDOSTERONISM
CONN SYNDROME (primary adrenal adenoma hypersecreting aldosterone)
What is the most common cause of SECONDARY HYPERALDOSTERONISM in females? in males?
FEMALES: FIBROMUSCULAR DYSPLASIA
MALES: ATHEROSCLEROSIS
Both are causes of renovascular HTN
How does one distinguish between PRIMARY and SECONDARY/TERTIARY ADRENAL INSUFFICIENCY in terms of clinical signs?
PRIMARY - YES hyperpigmentation, HYPERKALEMIA
SECONDARY/TERTIARY - NO hyperpigmentation, NO Hyperkalemia
What is the most common bacterial organism associated with ACUTE PRIMARY ADRENAL INSUFFICIENCY?
NEISSERIA MENINGITIDIS
What is the classic syndrome of ACUTE PRIMARY ADRENAL INSUFFICIENCY
WATERHOUES-FRIDERICHSEN SYNDROME
What is the most common cause of CHRONIC PRIMARY ADRENAL INSUFFICIENCY in the Western world?
Autoimmune destruction
What is the most common cause of CHRONIC PRIMARY ADRENAL INSUFFICIENCY in the developing world?
TB
What is the #1 cause of CUSHING SYNDROME?
EXOGENOUS CORTICOSTEROIDS
What is the most common tumor of the adrenal medulla in ADULTS?
PHEOCHROMOCYTOMA
What is the most common tumor of the adrenal medulla in children
NEUROBLASTOMA
What are the 90%s of PHEOCHROMOCYTOMA?
BOAS: Benign, onesided, adrenal only, sporadic
In 10% of the HEREDITARY PHEOCHROMOCYTOMA cases, what are the 3 common genetic mutations?
**RETgene mutation [proto-oncogene]- MEN2A/MEN2B
VHL
NF-1 gene [RAS oncogene regulator] - neurofibromatosis
Name the 3 carcinomas of MEN2A and MEN2B.
MEN2A: Medullary carcinoma of thyroid + Pheo + Parathyroid adenoma
MEN2B: “ + “ + ganglioneuroma of oral mucosa
VHL increases the risk of which 3 conditions?
- Renal cell carcinoma (RCC), 3pdel, CLEAR CELL VARIANT (CCC)
- Hemangioblastoma of the cerebellum
- Pheochromocytoma
What are the 3 main clinical features to look out for in PHEOCHROMOCYTOMA? Are PHEO pts volume depleted or volume overloaded?
PAROXYSMAL HTN
Cutaneous Pallor
Tachycardia/Palpitations
VOLUME DEPLETED
BROWN TUMOR. What should I think of?
PHEOCHROMOCYTOMA
What is the standard Tx protocol for a PHEOCHROMOCYTOMA Tx?
PHENOXYBENZAMINE or -zosins (alpha blockers) -> BETA BLOCKER -> Surgical Resection
Pharmacotherapy given before surgical resection to prevent hypertensive crisis during resection where touch can create a massive surge of E/NE that can be life-threatening
Pt comes in with TENDER THYROID. What should be on the top of your Ddx?
SUBACUTE GRANULOMATOUS (de QUERVAIN) Thyroiditis
40yo pts comes in with a NON-TENDER, hard as wood thyroid with dysphagia + Respiratory compromise. What does the pt MOST likely have?
RIEDEL FIBROSING THYROIDITIS
80yo pt comes in with NON-TENDER Thyroid with dysphagia + respiratory compromise. What does pt MOST likely have?
ANAPLASTIC CARCINOMA
Carcinomas generally like to spread to the lymph nodes. What are the 4 carcinoma exceptions to this general principle and likes instead to spread to the BLOOD (hematogenously)?
RENAL CELL CARCINOMA
HEPATOCELLULAR CARCINOMA
FOLLICULAR CARCINOMA
CHORIOCARCINOMA
Which lab findings particularly distinguish between PRIMARY and SECONDARY HYPERPARATHRYOIDISM?
PRIMARY - Excess PTH due to parathryoid adenoma (most common cause) - HYPERCALCEMIA, HYPOPHOSPHATEMIA
SECONDARY - Excess PTH due to chronic renal failure - HYPERPHOSPHATEMIA, binds up free Ca and thus HYPOCALCEMIA
Which hyper or hypo parathryoidism has INCREASED ALP? (alkaline phosphatase)
PRIMARY/SECONDARY/TERTIARY Hyperparathyroidism - all due to INCREASED PTH -> Increased osteoblast activity -> Increased ALP secretion
Ddx of HYPOCALCEMIA + INCREASED PTH
SECONDARY HYPERPARATHYROIDISM
PSEUDOHYPOPARATHYROIDISM (end organ resistance to PTH)
PERIORAL TINGLING + TROUSSEAU SIGN + CHVOSTEK SIGN
What am I?
HYPOPARATHYROIDISM
Trousseau and chvostek due to muscle spasm (tetany) + perioral tingle all due to hypocalcemia
What is the genetic defect of PSUEDOHYPOPARATHYROIDISM?
Genetic defect of Gs-alpha subunit (downstream mediator of PTH that results in cAMP activation) -> Develops end-organ resistance to PTH
What is the inheritance pattern of PSEUDOHYPOPARATHYROIDISM TYPE 1A (ALBRIGHT HEREDITARY OSTEODYSTROPHY)
AUTOSOMAL DOMINANT - inherited from mother by imprinting
Which PSEUDOHYPOPARATHYROIDISM is inherited from the father?
PSEUDOPSEUDOHYPOARATHYROIDISM
SHORT STATURE + SHORTENED 4th/5th digits
PSEUDOHYPOPARATHYROIDISM (BOTH TYPE 1A + PSEUDOPSUEDO)
What are the 2 differences between PSEUDOPSEUDOHYPOPARATHYROIDISM AND PSEUDOHYPOPARATHYROIDISM TYPE 1A?
PSEUDOPSEUDO: No end-organ resistance to PTH + Inheritance from father
Type 1A: YES, end-organ resistance to PTH + Inheritance from mother
Which type of DIABETES MELLITUS has a stronger genetic predisposition?
TYPE II DM
Obesity related to Type II DM is related to what aspect of the pathophysiology of NIDDM dvlm?
DECREASE IN INSULIN RECEPTORS
What is the genetic predisposition factor of TYPE I DM (IDDM)?
HLA DR-3, HLA-DR4
What are the 3 ways of diagnosing TYPE II DM (NIDDM)?
RANDOM GLC >200
FASTING GLC >126
GLC TOLERANCE TEST: GLC>200 2hrs after Glc loading
What are the 3 areas of OSMOTIC DAMAGE-mediated by TYPE II DM (NIDDM)?
- SCHWANN CELLS - No myelin production for PNS -> Peripheral neuropathy
- PERICYTES OF RETINAL BV -Weakening of retinal BV wall -> Aneurysm -> Rupture = hemorrhage
- LENS - Cataracts
These 3 are locations where insulin is NOT required for cellular Glc uptake.
ALDOSE REDUCTASE converts Glc to SORBITOL -> Induces osmotic damage
