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  #1  
Old 08-23-2012
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Question Which Hormone Affected?

A 15 yr old girl presents to the physician with underdeveloped breasts and hirsutism.. her medical history include menarche at age 12 and normal menses since then; her B.P is 90/55 mm hg..the enzyme deficient is needed for forming which hormone?
a) estrone
b) aldosterone
c) estradiol
d) testosterone
e) thyroxine



also tell me the enzyme deficient too?
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  #2  
Old 08-24-2012
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ruling out d) and e)

going with b) Aldosterone

mild 21-hydroxylase deficiency?
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Old 08-24-2012
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a or c ....
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Old 08-24-2012
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a) and c) would be a great answer choice
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Old 08-24-2012
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Underdeveloped breast hirsutism and regular menses ! !! ? whats the answer??
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Old 08-24-2012
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Default my answer

b) aldosterone
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Old 08-24-2012
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Weird...how can she present normal period cycle but with breast underdevelopment?

I go with estradiol.

Need explanation. Thanks!
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Old 08-24-2012
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It's either 17 or 21 hydroxylase deficiency

in 17 , normal female with lacking secondary characteristics (infantilism) but not hirsutism....plus this deficiency will cause decrease in both estrone and estradiol (a and c)

so it has to be 21-hydroxylase def. >> musculanizing symptoms like hirsutism
(a mild form!)

so it has to be b) aldosterone
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Old 08-24-2012
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My answer is b
patient has hypotension and masculinization so just in 21-hydroxylase deficiency hypotension is present(in 11- or 17-hydroxylase deficiency -hypertension)masculinization -in 21-and 11-hydroxylase deficiency(11-hydroxylase deficiency ruled out bcz patient is hypotensive ) . In 21 -hydroxylase deficiency decrease in mineralocorticoids:11-deoxycorticosterone,corticosterone and aldosterone
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Old 08-24-2012
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B as the case describe CAH. The defective enzyme is 21 hydroxylase.
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Old 08-24-2012
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I'm thinking it is because of aromatase deficiency.
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Old 08-24-2012
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Quote:
Originally Posted by irakly View Post
My answer is b
patient has hypotension and masculinization so just in 21-hydroxylase deficiency hypotension is present(in 11- or 17-hydroxylase deficiency -hypertension)masculinization -in 21-and 11-hydroxylase deficiency(11-hydroxylase deficiency ruled out bcz patient is hypotensive ) . In 21 -hydroxylase deficiency decrease in mineralocorticoids:11-deoxycorticosterone,corticosterone and aldosterone
If it is only 11-hydroxylase deficiency, it also can lead to hypotension. 11-hydroxylase deficiency will casue decrease in corticosterone, the precursor of aldosterone, so amount of aldosterone will also decrease. It is mainly the less amount of aldosterone that leads to the hypotension, right? And one more question, how to explain her breast underdevelopment?

Thanks!
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Old 08-24-2012
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Quote:
Originally Posted by belindalimm View Post
If it is only 11-hydroxylase deficiency, it also can lead to hypotension. 11-hydroxylase deficiency will casue decrease in corticosterone, the precursor of aldosterone, so amount of aldosterone will also decrease. It is mainly the less amount of aldosterone that leads to the hypotension, right? And one more question, how to explain her breast underdevelopment?

Thanks!
11 hydoxylase deficiency cause deccrease in CS production as the other forms of CAH but with this enzymatic defect there's a substare accumulation which's 11 deoxycorticosterone. This substrate has a potent mineralocorticoid activity that cause hypertension.
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Old 08-24-2012
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Quote:
Originally Posted by Anders View Post
11 hydoxylase deficiency cause deccrease in CS production as the other forms of CAH but with this enzymatic defect there's a substare accumulation which's 11 deoxycorticosterone. This substrate has a potent mineralocorticoid activity that cause hypertension.
May I know what is CAH and CS short for?
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Old 08-24-2012
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Quote:
Originally Posted by belindalimm View Post
May I know what is CAH and CS short for?

Sure, CAH = Congenital adrenal hyperplasia and CS= corticosteroid.
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Old 08-24-2012
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yes, the correct answer is B) aldosterone (classic 21 beta hydroxylase deficiency)

21 beta hydroxylase is the most common form of congenital adrenal hyperplasia in which there is mineralocorticoid and glucocorticoid deficient with excess of androgen production..due to increased precursors pregnenolone and progesterone...c/f---hypotension,hyponatremia, hypokalemia ,volume depletion , masculinization( as aromatase level is not elevated when compared to androgens).....
and female pseudo hermaphroditism (Patients with female pseudohermaphroditism have female internal genitalia and karyotype (XX) and various degree of external genitalia virilization(underdeveloped breasts, vagina ). External genitalia is musculinized congenitally when female fetus is exposed to excess androgenic environment. Congenital adrenal hyperplasia (CAH), mostly 21-hydroxylase deficiency, is the most common cause.Combination of hormonal therapy and surgical correction is required for CAH.)

and as for the other options...
exclusion is better.....all the other hormones require 17 alpha hydroxylase for their production ..so no associated hypotension is seen.....
so, as internal genitalia are female..menarche will be normal(but secondary amenorrhea is seen commonly)..the affected females are usually normal , of having usual capacity of all female roles( including child bearing)
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