Question

Lois, a 32-year old unmarried female business executive develops amenorrhea. She has not recently lost weight but states that her job is very stressful. Laboratory evaluation reveals the following results:

PARAMETER VALUE NORMAL RANGE

Serum estradiol 14pg/ml 23-145

LH 1.2mIU/ml 2-15

FSH 1.5mIU/ml 2-20

Prolactin 6.2ng/ml 2-25

TSH 1.2µU/ml 0.5-5.0

A serum pregnancy test is negative and an MRI scan of her pituitary gland is normal. What is the probable diagnosis? Explain. [6 marks]

Answer 1

ANSWER :

The probable diagnosis is Functional hypothalamic amenorrhea (FHA)

It is type of secondary amenorrhea and is classified as hypogonadotropic hypogonadism .It is related to an aberration of the pulsatile release of gonadotropin-releasing hormone (GnRH) from the hypothalamus .

EXPLANATION

Symptomatically patient is complaining of amenorrhea and gives history of stressful job. History of weight is important key to understand causes of amenorrhea [ as weight gain in PCOS, obesity etc].

• As a general measure of diagnosis ,even if the patient is unmarried pregnancy test is need to be ruled out in case of amenorrhea. For this patient it is negative.
• MRI for pituitary gland help to rule out abnormal pituitary gland ( like tumour growth etc). This patients MRI reports says normal.

• Lab diagnosis:

1. Serum Estradiol:
Estradiol is most active estrogen in body, secreted mainly by ovaries and in small amounts by adrenal glands. It works with progestrone to promote mensuration. Therefore estradiol level helps in diagnosis.
Since for this patient it is low ,there is chance of both PCOS(Polycystic Ovarian Syndrome) and FHA.

2. FSH and LH :
These are pituitary gland secreted hormones .
LH shows slight decrease in value while FSH falls within normal range.
This gives and idea that the condition is not PCOS as in PCOS LH levels will be high along with low estradiol. Therefore we can think of FHA .[Low LH level]

3.Prolactin : It is also pituitary hormone , which is necessary to tested inorder to give confirmation on pituitary gland tumour that can show similar symptoms like in PCOS and FHA.
Here the patient value shows normal .This can make us exclude pituitary causes completely.

4. TSH : Thyroid stimulating hormones secreted by thyroid glands. They are checked inorder to see whether there is underactive or overactive thyroid gland as these can cause anovulation, amenorrhea etc. TSH level also founds to be normal.

Based on all evidences w and stress as a main factor , we can conclude that patient likely developed FHA.The contributing factors to hypothalamic amenorrhea include energy imbalance, food restriction, weight loss, exercise, stress, and genetics.So here the cause is energy imbalance.