PITUITARY-PROLACTINOMA

SUMMARY

1. Most common microadenomas (< 1 cm).

2. Serum prolactin concentration > 200 ng/mL is indicative of a prolactinoma. Level of 21-40 ng/mL may be caused by drugs, pregnancy & lactation, food intake, hypothyroidism, CKD, chest wall injuries.

3. Inc PRL ⟹ dec GnRH ⟹ dec LH + FSH. This causes dec libido, galactorrhea (less common in men, more in women); amenorrhea, hirsuitism, decreased skeletal bone mineralization in both sexes.

4. Microadenoma management: dopamine agonist (bromocriptine, cabergoline). Both bromocriptine and cabergoline are FDA pregnancy
category B drugs.
5. Cabergoline is contraindicated in valvular, lung or retroperitoneal fibrotic diseases.

6. Macroadenoma management in threatened vision: surgery.

7. 1/3 of macroadenomas increase in pregnancy. Bromocriptine or surgery may be options in pregnancy.

Reference(s)

Wilkinson, I., Furmedge, D. and Sinharay, R. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press. Get it on Amazon.
Feather, A., Randall, D. and Waterhouse, M. (2020). Kumar And Clark’s Clinical Medicine. 10th ed. S.L.: Elsevier Health Sciences. Get it on Amazon.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].