Acromegaly and Prolactinoma - SRS Flashcards
Why would a female with acromegaly have abnormal menstrual cycles?
!!TQ here!!
Acromegaly may be accompanied by amenorrhea and galactorrhea because…
- GH stimulation of the prolactin receptor (both are cytokine receptors)
- GH may cosecrete prolactin (mammosomatotroph adenoma)
- Tumor may press on the pituitary stalk and block transit of dopamine
- Impaired gonadotropin secretion by the pituitary (d/t increased prolactin suppression)
What are the causes of a positive Tinel’s sign?
Which one would apply in this class?
Mnenonic is “Median Trap”
- Myxedema
- Edema
- Diabetes
- Infiltration
- Amyloid
- Neoplasms
- Trauma
- Acromegaly
- Pregnancy
What type of headache is worse with coughing, associated with nausea and worse on arising?
Those caused by a brain tumor
Why the acanthosis nigricans and skin tags in patients with acromegaly?
D/t insulin resistance and excess IGF-1
When testing for acromegaly we do what challenge?
What would a positive result be?
What would you do next?
75g glucose challenge, check glucose and GH levels every 30 minutes post administration - positive if this fails to suppress GH to less than 1 ng/mL.
THEN, if positive order an MRI.
What are the causes of acromegaly?
3
- Microadenoma with somatotroph mutation
- Macroadenoma
- Ectopic GH or GHRH production
What are some examples of cancers that cause ectopic production of GH or GHRH?
6
- Carcinoid
- Pancreas
- Lung
- Ovary
- Breast
- Lymphoma
Acromegaly and giantism may be associated with what syndromes?
- MEN 1 ( 3 Ps with hypercalcemia, peptic ulcer, or hypoglycemia).
- Carney complex ( mutation in tumor suppressor gene for protein kinase A).
- MuCune-Albright syndrome (Polyostotic fibrous dysplasia, café au lait, endocrine hyperfunction).
What does this child who is at risk of gigantism have?
McCune Albright Syndrome - Polyostotic fibrous dysplasia, café au lait, endocrine hyperfunction
What are 3 associated complication types of a GH secreting adenoma?
- Pressure effects (headache, visual alterations, etc).
- Additional hormone production (cosecretion of prolactin).
- Interference with other hormones (decreased ACTH, TSH, etc).
List for me 8 comorbidities associated with Acromegaly.
- Sleep apnea
- Hypertension
- Diabetes
- Cardiomyopathy
- Colon polyps
- Degenerative joint disease
- Thyroid nodules
- Premature mortality
Based on the comorbidities associated with a GH adenoma, what are three tests you should consider doing?
List why for each.
ECHO - test for cardiomyopathy
Colonoscopy - Colon Polyps common
Vertebral Xray - degenerative joint disease seen here
What are some options for pharm tx of GH adenomas?
7 options, 6 of which are on our drug list
- Bromocriptine - DA agonist
- Cabergoline - DA agonist
- Octreotide - SST analogue
- Lanreotide - SST analogue
- Pasireotide - SST analogue
- Pegvisomat - GH receptor antagonist
Apart from the pharm tx, what other options are there to deal with an adenoma?
- Surgery
- Radiation
If you send a pt to undergo transphenoidal surgery for removal of a GH adenoma, and they only find hyperplasia, what should you do?
Look for an ectopic source of either GH or GHRH