1. Hormone Replacement Therapy in Men
Larry Oteham, D.O.
DME and Family Medicine Residency Director
Lake Cumberland Regional Hospital
Somerset, Kentucky

2. Disclosures
Regretably, I have nothing to disclose.

3. Harvey, a 52 year old male presents for evaluation and treatment of erectile dysfunction. While watching an old episode of Walker Texas Ranger, he saw a commercial that suggested he might have low-T. He reflected on how fit Chuck Norris looked and wondered if you could check his testosterone.

4. Being an astute physician, you take a history and examine him
Being an astute physician, you take a history and examine him. He has a BMI of 37, has had elevated liver enzymes that were attributed to fatty liver. He is a non-smoker with a normal PSA. He takes synthroid for hypothyroidism, but otherwise no medicine. He has occational spontaneous erections but cannot maintain an erection.
Physical exam is unremarkable.

5. Laboratory analysis includes:
Normal PSA (2.0)
AM Total Testosterone of 185 Normal range ( )
CBC normal
CMP normal
FSH and LH range normal
Prolactin normal
TSH

6. Should Harvey be treated with supplemental testosterone?
Yes or No

7. What are the other considerations?

8. The sex hormone binding globulin (SHBG) test may be used to help evaluate men for low testosterone and women for excess testosterone production. It may be ordered in conjunction with other tests to evaluate the status of a person's sex hormones.
© by American Association for Clinical Chemistry 

9. SHBG is a protein that binds tightly to the hormones testosterone, dihydrotestosterone (DHT), and estradiol (an estrogen). In this bound state, SHBG transports these hormones in the blood as biologically inactive forms. Changes in SHBG levels can affect the amount of hormone that is available to be used by the body's tissues.
© by American Association for Clinical Chemistry 

10. Testing for albumin level and one or more other sex hormones, such as prolactin, estradiol, and LH (luteinizing hormone), may also be performed to evaluate a person's existing balance of hormones.
© by American Association for Clinical Chemistry 

11. SHBG in men SHBG and total testosterone levels may be ordered for an adult male to help determine the cause of infertility, a decreased sex drive, or erectile dysfunction. Measurement of SHBG in addition to testosterone is especially helpful when total testosterone results are inconsistent with clinical signs.
© by American Association for Clinical Chemistry 

12. Measurement of total testosterone in the blood does not distinguish between bound and unbound (bioavailable) testosterone but, as the name implies, determines the overall quantity of testosterone in the blood. In many cases, this is sufficient to evaluate excessive or deficient testosterone production.
© by American Association for Clinical Chemistry 

13. However, if a person's SHBG level is not normal, then the total testosterone may not be an accurate representation of the amount of testosterone that is available to the body's tissues.
© by American Association for Clinical Chemistry 

14. Measurement of SHBG helps health practitioners assess bioavailable testosterone with a simple total testosterone measurement. Increased SHBG in men may be associated with symptoms of low testosterone levels (hypogonadism) because less testosterone is available to the body's tissues.
© by American Association for Clinical Chemistry 

15. The Endocrine Society professional guidelines recommend measuring total testosterone in the initial screen for testosterone deficiency. If abnormal, the test is repeated on another day
© by American Association for Clinical Chemistry 

16. recommend one of the following:
If repeat results are low-normal and/or if SHBG is abnormal, they recommend one of the following:
recommend one of the following:
© by American Association for Clinical Chemistry 

17. Calculate free testosterone from total testosterone and SHBG
Measure bioavailable testosterone (using ammonium sulfate precipitation or SHBG)
Calculate free testosterone from total testosterone and SHBG
Measure free testosterone (using a method called equilibrium dialysis)
© by American Association for Clinical Chemistry 

18. When is it ordered?
SHBG is ordered primarily when the total testosterone results do not seem to be consistent with clinical signs and symptoms, such as infertility, decreased sex drive, and erectile dysfunction in men or infertility, irregular menstrual periods, and excess facial and body hair in women.
© by American Association for Clinical Chemistry 

19. What does the test result mean?
A high SHBG level means that it is likely that less free testosterone is available to the tissues than is indicated by the total testosterone test.
© by American Association for Clinical Chemistry 

20. What does the test result mean?
A low SHBG level means that more of the total testosterone is bioavailable and not bound to SHBG.
© by American Association for Clinical Chemistry 

21. What does the test result mean?
© by American Association for Clinical Chemistry 

22. Increased SHBG levels may be seen in:
Liver disease
Hyperthyroidism
Eating disorders (anorexia nervosa)
Corticosteroids or estrogen use (hormone replacement therapy and oral contraceptives)
Decreased sex hormone production (hypogonadism)
Pregnancy
© by American Association for Clinical Chemistry 

23. Polycystic ovary syndrome Hypothyroidism Androgen (steroid) use
Decreases in SHBG are seen with:
Obesity
Polycystic ovary syndrome
Hypothyroidism
Androgen (steroid) use
Cushing disease
© by American Association for Clinical Chemistry 

24. Is there anything else I should know?
SHBG concentrations are normally high in children of both sexes. After puberty, SHBG levels decrease more rapidly in males than in females.
© by American Association for Clinical Chemistry 

25. Is there anything else I should know?
Levels are normally stable in adults and then begin to increase in the elderly male at the same time that total testosterone levels begin to decrease.
© by American Association for Clinical Chemistry 

26. Is there anything else I should know?
In postmenopausal women, SHBG, testosterone, and estrogen concentrations decrease as hormone production by the ovaries tapers off.
© by American Association for Clinical Chemistry 

27. References:
© by American Association for Clinical Chemistry
Roberta B. Carey, PhD, D (ABMM), CMQ/OE (ASQ) Former Director of Laboratory Quality Management Program Centers for Disease Control and Prevention Atlanta, GA Affiliation: American Society for Microbiology This activity is being performed by Roberta B. Carey, PhD in her private capacity
Anne Chenoweth, MBA, MT(ASCP)CM, CQA(ASQ) Director, Accreditation and Quality, AABB Bethesda, MD Affiliation: AABB
Alicia Diaz-Thomas, MD, MPH Assistant Professor, Pediatrics Program Director, Pediatric Endocrinology Fellowship University of Tennessee Health Science Center Memphis, TN Affiliation: Endocrine Society
Etal.