CC 1 - Sheehan's Syndrome

Question 1

What is Sheehan’s syndrome?

Answer 1

Blood loss and hypovolemic shock during and after childbirth => decreased blood to the anterior pituitary (especially cause it receives a low pressure venous blood supply) => postpartum hypopituitarism or postpartum pituitary gland necrosis caused by ischemic necrosis => no breast milk production because no prolactin + no body hair because no adrenal androgens because no ACTH

Question 2

Why do Sheehan’s syndrome patients exhibit permanent amenorrhea?

Answer 2

Lack of LH/FSH output by pituitary => no estrogen/progesterone

Question 3

Why do Sheehan’s syndrome patients exhibit atrophy of the breasts?

Answer 3

Lack of LH/FSH output by pituitary => low estrogen

Question 4

Why do Sheehan’s syndrome patients exhibit excessive fatigue and lethargy?

Answer 4

1. Low TSH

2. Low ACTH => low cortisol

Question 5

BP of patients with Sheehan’s syndrome? Explain.

Answer 5

Low because of low BV due to low cortisol which helps mineralcorticoids, therefore low NaCl/H2O reabsorption by the kidney

Question 6

Why would a doctor check visual fields of a patient with Sheehan’s syndrome?

Answer 6

To make sure there is no pituitary tumor compressing the optic nerves

Most common: prolactenoma

Question 7

Why do Sheehan’s syndrome patients exhibit small thyroid?

Answer 7

Low TSH

Question 8

Why do Sheehan’s syndrome patients exhibit decreased vaginal secretions?

Answer 8

Lack of LH/FSH output by pituitary => low estrogen => normally stimulates growth of vaginal epithelium and secretions

Question 9

Why do Sheehan’s syndrome patients exhibit a small uterus?

Answer 9

Lack of LH/FSH output by pituitary => low estrogen => normally stimulates growth of myometrium and endometrium

Question 10

Why do Sheehan’s syndrome patients exhibit non palpable adnexa? What does this mean?

Answer 10

No palpable ovaries => reduced ovarian size due to low FSH/LH => low tropic effect

Question 11

What does it mean for FSH/LH to be tropic hormones?

Answer 11

They cause endocrine secretions and maintain the size and structure of the target glands

Question 12

Why do Sheehan’s syndrome patients exhibit excessive pale pigment in skin and areola?

Answer 12

Low ACTH => low alpha-MSH

Question 13

Why do Sheehan’s syndrome patients exhibit small cardiac silhouette?

Answer 13

1. Low BV
2. Low TSH => low adrenergic receptors on cardiovascular tissue => low sympathetic stimulation of the heart
3. Low GH => decreased organ size, including the heart

Question 14

Why do Sheehan’s syndrome patients exhibit small sella turcica?

Answer 14

Small anterior pituitary gland in that space

Question 15

Is the posterior pituitary affected by Sheehan’s syndrome?

Answer 15

Rarely because different blood supply: arterial so can better regulate blood flow

Question 16

Why are cortisol levels provided with a time stamp on lab reports?

Answer 16

Largest cortisol peak is at 8 am, so that is when measurements should be done

Question 17

Normal LH and FSH levels?

Answer 17

4-30 mLU/mL

Question 18

Normal estradiol premenopause?

Answer 18

> 25 pg/mL

Question 19

Normal 8 am cortisol?

Answer 19

7-18 microg/dL

Question 20

What is an insulin challenge? What values are looked at?

Answer 20

Infuse insulin => hypoglycemia => monitor ACTH and GH, which should both be stimulated to increase cortisol and glucose levels as both are hyperglycemic hormones

Question 21

Why would you give TRH to patients with Sheehan’s disease?

Answer 21

Very high levels to try to induce prolactin secretion, even though it is not a physiological stimulator of prolactin release

+ induce TSH secretion

=> diagnostic test

Question 22

Can some anterior pituitary neuron clusters be more affected than other by Sheehan’s syndrome? Explain.

Answer 22

YUP

There can be a functional deficit of some hormones, not a total deficit like others

Question 23

What is metarypone? Why would you use it on a Sheehan’s syndrome patient?

Answer 23

Cortisol synthesis inhibitor

Lower cortisol => induce ACTH release BUT this would cause very low cortisol and vascular collapse: BP goes to 0, insufficient blood flow and nutrients to the brain, sometimes fatal

Question 24

Can you treat patients with Sheehan’s syndrome with GHRH and GnRH?

Answer 24

NOPE, not ant pit to secrete GH and FSH/LH

Question 25

Treatment of Sheehan’s syndrome? What to note?

Answer 25

1. Cortisol
2. T3/T4
3. Estrogen/progesterone for better quality of life
4. Androgens for hair and well-being, confidence

Note: we do not treat with pituitary hormones because they are peptides and would need to be injected and they are SO expensive BUT would be needed if patient wants to become pregnant

Question 26

Is Sheehan’s syndrome common in the US?

Answer 26

No very rare because birth done in a controlled setting