Reference no: EM133496260

Assignment:

Case Study: Acromegaly

Pooja is a 42-year-old sales executive. She travels constantly and prides herself on being energetic and surpassing sales projections each quarter. Three years ago, she developed irregular menses, and she then she completely stopped menstruating. Over the past two years, she has begun to feel increasingly fatigued, has difficulty rushing the length of the airport terminals, and is bothered by frequent headaches. She has always had a firm handshake, but lately has noticed that her wedding ring is excessively tight. Pooja is also frustrated that she has recently had to replace her entire shoe collection because her shoe size has increased from 7.5 to 9, with a need for increased width as well. Additionally, she has noticed increased perspiration, even when she is not exerting herself, and increased spacing between her teeth. Concerned about her progressive cosmetic changes and her lack of menses, Pooja turns to Google for information and comes across a condition called acromegaly.

Struck by the uncanny resemblances between her complaints and those she has read about on Google, Pooja goes to see her doctor for further evaluation. A serum insulin-like growth factor (IGF-1) level is significantly elevated after correction for Pooja's age and sex, and her serum growth hormone (GH) level is 10 ng/mL (normal <1 ng/mL) after an oral glucose load of 75 mg. A magnetic resonance imaging (MRI) study of her head reveals a pituitary adenoma with a maximal diameter of 1.5 cm. These findings are consistent with a diagnosis of acromegaly due to a GH-secreting adenoma. Pooja receives transsphenoidal pituitary surgery. Despite tolerating the surgery well, Pooja's postoperative IGF-1 and GH levels remain elevated.

Based on the continued elevations in serum GH and IGF-1, Pooja's endocrinologist recommends medical treatment with a depot ocreotide injections. After 6 months of depot ocreotide injections, Pooja's GH and IGF-1 levels remain elevated and Pooja is frustrated by the lack of improvement. However, she does feel that she has more energy than before, and her menses have resumed. Pooja's endocrinologist recommends treatment with pegvisomant as an alternative medical approach. Pooja begin daily injections with pegvisomant and six months later, her IGF-1 level is in the normal range. She resumes her normal life and continues to receive yearly head MRI and liver function tests.

Questions ( dont answer from AI please, EVERYTHING SHOULD BE FROM THE TEXTBOOK)

1. Why did Pooja develop enlarged extremities rather than an increase in height in response to her elevated GH levels?

2. What was the likely cause of Pooja's amenorrhea?

3. Describe the relationship between GH and IGF-1 and the metabolic effects of both hormones

4. Why were serum levels of IGF-1 a more appropriate screening test for acromegaly than GH levels?

5. What is the purpose of the oral glucose load given to Pooja prior to measuring her plasma GH levels?

6. How do ocreotide and pegvisomant act to lower GH levels?