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What Does The Following IGF-1 Laboratory Test Result Indicate?
Question: Dear Dr. XXXXXXX Parameswaran XXXXXXX Thank you for your responses. I am attaching the IGF-1 lab result. 1st available appt w/endocrinologist is Oct. 28 :-(
Brief Answer:
Normal IGF 1 levels.
Detailed Answer:
Good day.
Thank you for the follow up question. Your IGF 1 is very much in normal range. No need to worry. Based on this, you do not have growth hormone deficiency.
Regards
Binu
Normal IGF 1 levels.
Detailed Answer:
Good day.
Thank you for the follow up question. Your IGF 1 is very much in normal range. No need to worry. Based on this, you do not have growth hormone deficiency.
Regards
Binu
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
So, do you have any other thoughts as to why my TSH level is nearly nonexistent while all other thyroid levels are all low normal (see correspondence with you). My 53 mile bike ride 2 days ago burned over 1500 calories. We live on a farm. I am very, very active and eat an extremely healthy diet. We fish & hunt, raise black XXXXXXX cattle, have a beautiful garden. In the last 2 days I have gained another 1.5 lbs. i know that something is wrong. You are the only dr. that has given me some hope of finding the problem. There are no appt. available with endocrinologist until Oct. 29. I am truly beyond frustrated and distraught. I did have a cortisol test sone time ago that was also normal. I am hopeful you have some additional thoughts to resolving my health issue. My Family Physician is fantastic and I am certain he would follow through with recommendations you have. Kind Regards, XXXX
Brief Answer:
Cyclical Cushings syndrome
Detailed Answer:
Thank you for the reply. Noted the history and happy to hear about your active life style. Now we have only few explanations for low TSH
1) Depression or stress: this can reduce the TSH levels.
2) Use of medicines which can supress TSH levels ( most importantly steroids). Are you on any of these?
3) Excess cortisol production in body.
2 and 3 can explain your weight gain as well.
you need to do couple of special tests.
a) 24 hour urine free cortisol.
b) Overnight dexamethasone supression test
c) Midnight salivary cortisol.
Your doctor can select any one of the above tests to rule out excess cortisol production in your body ( Cushings syndrome).
MOST IMPORTANT AND OFTEN Undiagnosed cause of low TSH and weight gain is episodic excess production of cortisol called as Cyclical Cushing's syndrome. This need high clinical suspicion and you may need to do midnight salivary cortisol for several days to demonstrate this. I dot know if your family physician is familiar with this condition ( Sub clinical Cushings syndrome).
Apart from this, you may also need an MRI scan of pituitary to rule out central hypothyroidism as a cause of low TSH.
Your physician may discuss with an endocrinologist over phone these points ( considering that there is delay in an endocrine consultation)
Cyclical Cushings syndrome
Detailed Answer:
Thank you for the reply. Noted the history and happy to hear about your active life style. Now we have only few explanations for low TSH
1) Depression or stress: this can reduce the TSH levels.
2) Use of medicines which can supress TSH levels ( most importantly steroids). Are you on any of these?
3) Excess cortisol production in body.
2 and 3 can explain your weight gain as well.
you need to do couple of special tests.
a) 24 hour urine free cortisol.
b) Overnight dexamethasone supression test
c) Midnight salivary cortisol.
Your doctor can select any one of the above tests to rule out excess cortisol production in your body ( Cushings syndrome).
MOST IMPORTANT AND OFTEN Undiagnosed cause of low TSH and weight gain is episodic excess production of cortisol called as Cyclical Cushing's syndrome. This need high clinical suspicion and you may need to do midnight salivary cortisol for several days to demonstrate this. I dot know if your family physician is familiar with this condition ( Sub clinical Cushings syndrome).
Apart from this, you may also need an MRI scan of pituitary to rule out central hypothyroidism as a cause of low TSH.
Your physician may discuss with an endocrinologist over phone these points ( considering that there is delay in an endocrine consultation)
Note: For further follow up on related General & Family Physician Click here.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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