Endo: Adrenal Disorders 2

Question 1

What controls the adrenal medulla?

Answer 1

Sympathetic nervous system

Question 2

Name the intermediates and enzymes in epinephrine production

Answer 2

1. Tyrosine is converted to DOPA
   
   • by Tyrosine Hydroxylase
2. DOPA is converted to Dopamine
   
   • by DOPA decarboxylase
3. Dopamine is converted to Norepi
   
   • By dopamine beta hydroxylase
4. Norepi is converted to Epi
   
   • by PMNT

Question 3

What cell type gives rise to pheochromocytomas?

Embryologic origin?

Answer 3

Chromaffin cells (neural crest)

Question 4

Compare paraganglioma and pheochromocytoma

Answer 4

• Paragangliomas: tumor of sympathetic or parasympathetic neurons
• Pheochromocytoma: tumor of adrenal medulla

Both can produce excess catecholamines

Question 5

What is the classic triad of pheochromocytoma symptoms?

Answer 5

Headache

sweating

palpitations

Question 6

How do we diagnose pheochromocytomas? (2)

Answer 6

• Plasma metanephrines more than 2-3x upper limit of normal
• Can also do urine metanephrines

Question 7

Which of these medications interfere with metanephrine testing?

• Acetaminophen
• Buspirone
• TCAD
• Ibuprofen
• Ondansetron
• SSRI/SNRI
• Marijuana
• Metoclopramide

Answer 7

• Acetaminophen
• TCAD
• SSRI/SNRI
• Marijuana

Question 8

Tx for pheochromocytoma

Answer 8

• Blockade prior to surgery
  
  • Alpha blockers (eg. phenoxybenzamine, doxazosin)
  • Followed by beta blockers

Question 9

Name 3 conditions associated with pheochromocytoma

Answer 9

• VHL (Von-Hippel Lindau Syndrome)
• NF-1 (Neurofibromatosis I)
• RET (Multiple Endocrine Neoplasia 2)

Question 10

MEN 1

• types of tumors
• mutation/inheritance

Answer 10

• Pituitary, Parathryoid, Pancreas tumors
• Autosomal dominant mutation in MEN gene on chromosome 11

Question 11

MEN2A

• tumors
• mutation

Answer 11

• Parathyroid, Pheochromocytoma, Medullary thryoid carcinoma (C cell tumor)
• RET mutation

Question 12

MEN2B

• tumors/features
• mutation

Answer 12

• Pheochromocytoma, Medullary thryoid cancer, Mucosal neuroma, Marfanoid habitus
• RET mutation

Question 13

What is the inheritance of Multiple Endocrine Neoplasia?

Answer 13

ALL autosomal dominant

(all MEN think they’re dominant)

Question 14

What does the Hounsfield scale (HU) tell us on imaging of the adrenals?

Answer 14

• HU is a measure of the intracellular lipids
• HU < 10 indicates that an adrenal mass is mostly water/fat and is likely benign adrenal nodule

Question 15

Compare the washout on adrenal CT for cortical adenomas and pheochromocytomas

Answer 15

• Cortical adenomas (benign) have HIGH washout
• Pheochromocytomas have LOW washout