Test Catalog

Test Id : TGRP

Testosterone, Total and Free, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Alternative, second-level test for suspected increases or decreases in physiologically active testosterone:

-Assessment of androgen status in cases with suspected or known sex hormone-binding globulin-binding abnormalities

-Assessment of functional circulating testosterone in early pubertal boys and older men

-Assessment of functional circulating testosterone in women with symptoms or signs of hyperandrogenism, but normal total testosterone levels

-Monitoring of testosterone therapy or antiandrogen therapy in older men and in females

Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.

Test Id Reporting Name Available Separately Always Performed
FRTST Testosterone, Free, S No Yes
TTST Testosterone, Total, S Yes Yes

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Method Name
A short description of the method used to perform the test

FRTST: Equilibrium Dialysis

TTST: Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Testosterone, Total and Free, S

Aliases
Lists additional common names for a test, as an aid in searching

TGRP

Specimen Type
Describes the specimen type validated for testing

Serum Red

Ordering Guidance

This is a second-level test for suspected increases or decreases in physiologically active testosterone. The preferred test for assessment of active testosterone is TTBS / Testosterone, Total and Bioavailable, Serum.

Necessary Information

Patient's age and sex are required.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Container/Tube: Red top (serum gel/SST are not acceptable)

Specimen Volume: 2.5 mL

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Forms

If not ordering electronically, complete, print, and send a General Request (T239) with the specimen.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

1 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia Reject
Gross icterus Reject

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Red Refrigerated (preferred) 14 days
Frozen 60 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Alternative, second-level test for suspected increases or decreases in physiologically active testosterone:

-Assessment of androgen status in cases with suspected or known sex hormone-binding globulin-binding abnormalities

-Assessment of functional circulating testosterone in early pubertal boys and older men

-Assessment of functional circulating testosterone in women with symptoms or signs of hyperandrogenism, but normal total testosterone levels

-Monitoring of testosterone therapy or antiandrogen therapy in older men and in females

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Testosterone is the major androgenic hormone. It is responsible for the development of the male external genitalia and secondary sexual characteristics. In females, its main role is as an estrogen precursor. In both genders, it also exerts anabolic effects and influences behavior.

 

In men, testosterone is secreted by the testicular Leydig cells and, to a minor extent, by the adrenal cortex. In premenopausal women, the ovaries are the main source of testosterone with minor contributions by the adrenals and peripheral tissues. After menopause, ovarian testosterone production is significantly diminished. Testosterone production in testes and ovaries is regulated via pituitary-gonadal feedback involving luteinizing hormone (LH) and, to a lesser degree, inhibins and activins.

 

Most circulating testosterone is bound to sex hormone-binding globulin (SHBG), which, in men, also is called testosterone-binding globulin. A lesser fraction is albumin bound and a small proportion exists as free hormone. Historically, only free testosterone was thought to be the biologically active component. However, testosterone is weakly bound to serum albumin and dissociates freely in the capillary bed, thereby becoming readily available for tissue uptake. All non-SHBG-bound testosterone is therefore considered bioavailable.

 

During childhood, excessive production of testosterone induces premature puberty in boys and masculinization in girls. In adult women, excess testosterone production results in varying degrees of virilization, including hirsutism, acne, oligo-amenorrhea, or infertility. Mild-to-moderate testosterone elevations are usually asymptomatic in males but can cause distressing symptoms in females. The exact causes for mild-to-moderate elevations in testosterone often remain obscure. Common causes of pronounced elevations of testosterone include genetic conditions (eg, congenital adrenal hyperplasia); adrenal, testicular, and ovarian tumors; and abuse of testosterone or gonadotrophins by athletes.

 

Decreased testosterone in females causes subtle symptoms. These may include some decline in libido and nonspecific mood changes. In males, it results in partial or complete degrees of hypogonadism. This is characterized by changes in male secondary sexual characteristics and reproductive function. The cause is either primary or secondary/tertiary (pituitary/hypothalamic) testicular failure. In adult men, there also is a gradual modest but progressive decline in testosterone production starting between the fourth and sixth decades of life. Since this is associated with a simultaneous increase of SHBG levels, bioavailable testosterone may decline more significantly than apparent total testosterone, causing nonspecific symptoms similar to those observed in testosterone deficient females. However, severe hypogonadism, consequent to aging alone, is rare.

 

Measurement of total testosterone (TTST / Testosterone, Total, Mass Spectrometry, Serum) is often sufficient for diagnosis, particularly if it is combined with measurements of LH and follicle-stimulating hormone (FSH) (LH / Luteinizing Hormone [LH], Serum and FSH / Follicle-Stimulating Hormone [FSH], Serum). However, these tests may be insufficient for diagnosis of mild abnormalities of testosterone homeostasis, particularly if abnormalities in SHBG (SHBG / Sex Hormone-Binding Globulin [SHBG], Serum) function or levels are present. Additional measurements of free testosterone or bioavailable testosterone are recommended in this situation; bioavailable (TTBS / Testosterone, Total and Bioavailable, Serum) is the preferred assay.

 

See Steroid Pathways in Special Instructions.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

TESTOSTERONE, FREE

Males (adult):

20-<25 years: 5.25-20.7 ng/dL

25-<30 years: 5.05-19.8 ng/dL

30-<35 years: 4.85-19.0 ng/dL

35-<40 years: 4.65-18.1 ng/dL

40-<45 years: 4.46-17.1 ng/dL

45-<50 years: 4.26-16.4 ng/dL

50-<55 years: 4.06-15.6 ng/dL

55-<60 years: 3.87-14.7 ng/dL

60-<65 years: 3.67-13.9 ng/dL

65-<70 years: 3.47-13.0 ng/dL

70-<75 years: 3.28-12.2 ng/dL

75-<80 years: 3.08-11.3 ng/dL

80-<85 years: 2.88-10.5 ng/dL

85-<90 years: 2.69-9.61 ng/dL

90-<95 years: 2.49-8.76 ng/dL

95-100+ years: 2.29-7.91 ng/dL

 

Males (children):

<1 year: Term infants

 

1-15 days: 0.20-3.10 ng/dL*

16 days-1 year: Values decrease gradually from newborn (0.20-3.10 ng/dL) to prepubertal levels

*Citation: J Clin Endocrinol Metab 1973;36(6):1132-1142

 

1-8 years: <0.04-0.11 ng/dL

9 years: <0.04-0.45 ng/dL

10 years: <0.04-1.26 ng/dL

11 years: <0.04-5.52 ng/dL

12 years: <0.04-9.28 ng/dL

13 years: <0.04-12.6 ng/dL

14 years: 0.48-15.3 ng/dL

15 years: 1.62-17.7 ng/dL

16 years: 2.93-19.5 ng/dL

17 years: 4.28-20.9 ng/dL

18 years: 5.40-21.8 ng/dL

19 years: 5.36-21.2 ng/dL

 

Females (adult):

20-<25 years: 0.06-1.08 ng/dL

25-<30 years: 0.06-1.06 ng/dL

30-<35 years: 0.06-1.03 ng/dL

35-<40 years: 0.06-1.00 ng/dL

40-<45 years: 0.06-0.98 ng/dL

45-<50 years: 0.06-0.95 ng/dL

50-<55 years: 0.06-0.92 ng/dL

55-<60 years: 0.06-0.90 ng/dL

60-<65 years: 0.06-0.87 ng/dL

65-<70 years: 0.06-0.84 ng/dL

70-<75 years: 0.06-0.82 ng/dL

75-<80 years: 0.06-0.79 ng/dL

80-<85 years: 0.06-0.76 ng/dL

85-<90 years: 0.06-0.73 ng/dL

90-<95 years: 0.06-0.71 ng/dL

95-100+ years: 0.06-0.68 ng/dL

 

Females (children):

<1 year: Term infants

 

1-15 days: 0.06-0.25 ng/dL*

16 days-1 year: Values decrease gradually from newborn (0.06-0.25 ng/dL) to prepubertal levels

*Citation: J Clin Endocrinol Metab, 36(6):1132-1142, 1973

 

1-4 years: <0.04 ng/dL

5 years: <0.04-0.07 ng/dL

6 years: <0.04-0.14 ng/dL

7 years: <0.04-0.23 ng/dL

8 years: <0.04-0.34 ng/dL

9 years: <0.04-0.46 ng/dL

10 years: <0.04-0.59 ng/dL

11 years: <0.04-0.72 ng/dL

12 years: <0.04-0.84 ng/dL

13 years: <0.04-0.96 ng/dL

14 years: <0.04-1.06 ng/dL

15-18 years: <0.04-1.09 ng/dL

19 years: 0.06-1.08 ng/dL

 

TESTOSTERONE, TOTAL

Males

0-5 months: 75-400 ng/dL

6 months-9 years: <7-20 ng/dL

10-11 years: <7-130 ng/dL

12-13 years: <7-800 ng/dL

14 years: <7-1,200 ng/dL

15-16 years: 100-1,200 ng/dL

17-18 years: 300-1,200 ng/dL

> or =19 years: 240-950 ng/dL

Tanner Stages*

I (prepubertal): <7-20

II: 8-66

III: 26-800

IV: 85-1,200

V (young adult): 300-950

 

Females

0-5 months: 20-80 ng/dL

6 months-9 years: <7-20 ng/dL

10-11 years: <7-44 ng/dL

12-16 years: <7-75 ng/dL

17-18 years: 20-75 ng/dL

> or =19 years: 8-60 ng/dL

Tanner Stages*

I (prepubertal): <7-20

II: <7-47

III: 17-75

IV: 20-75

V (young adult): 12-60

Interpretation
Provides information to assist in interpretation of the test results

Total testosterone and general interpretation of testosterone abnormalities:

 

In male patients:

Decreased testosterone levels indicate partial or complete hypogonadism. Serum testosterone levels are usually below the reference range. The cause is either primary or secondary/tertiary (pituitary/hypothalamic) testicular failure.

 

Primary testicular failure is associated with increased luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, and decreased total, bioavailable, and free testosterone levels. Causes include:

-Genetic causes (eg, Klinefelter syndrome, XXY males)

-Developmental causes (eg, testicular maldescent)

-Testicular trauma or ischemia (eg, testicular torsion, surgical mishap during hernia operations)

-Infections (eg, mumps)

-Autoimmune diseases (eg, autoimmune polyglandular endocrine failure)

-Metabolic disorders (eg, hemochromatosis, liver failure)

-Orchidectomy

 

Secondary/tertiary hypogonadism, also known as hypogonadotrophic hypogonadism, shows low testosterone and low, or inappropriately "normal," LH/FSH levels; causes include:

-Inherited or developmental disorders of hypothalamus and pituitary (eg, Kallmann syndrome, congenital hypopituitarism)

-Pituitary or hypothalamic tumors

-Hyperprolactinemia of any cause

-Malnutrition or excessive exercise

-Cranial irradiation

-Head trauma

-Medical or recreational drugs (eg, estrogens, gonadotropin releasing hormone [GnRH] analogs, cannabis)

 

Increased testosterone levels:

-In prepubertal boys, increased levels of testosterone are seen in precocious puberty. Further workup is necessary to determine the causes of precocious puberty.

-In adult men, testicular or adrenal tumors or androgen abuse might be suspected if testosterone levels exceed the upper limit of the normal range by more than 50%.

 

Monitoring of testosterone replacement therapy:

Aim of treatment is normalization of serum testosterone and LH. During treatment with depot-testosterone preparations, trough levels of serum testosterone should still be within the normal range, while peak levels should not be significantly above the normal young adult range.

 

Monitoring of antiandrogen therapy:

Aim is usually to suppress testosterone levels to castrate levels or below (no more than 25% of the lower reference range value).

 

In female patients:

Decreased testosterone levels may be observed in primary or secondary ovarian failure, analogous to the situation in men, alongside the more prominent changes in female hormone levels. Most women with oophorectomy have a significant decrease in testosterone levels.

 

Increased testosterone levels may be seen in:

-Congenital adrenal hyperplasia: non-classical (mild) variants may not present in childhood but during or after puberty. In addition to testosterone, multiple other androgens or androgen precursors are elevated, such as 17-hydroxyprogesterone (OHPG / 17-Hydroxyprogesterone, Serum), often to a greater degree than testosterone.

-Prepubertal girls: analogous to males, but at lower levels, increased levels of testosterone are seen in precocious puberty.

-Ovarian or adrenal neoplasms: high estrogen values also may be observed, and LH and FSH are low or "normal." Testosterone-producing ovarian or adrenal neoplasms often produce total testosterone values above 200 ng/dL.

-Polycystic ovarian syndrome: hirsutism, acne, menstrual disturbances, insulin resistance and, frequently, obesity, form part of this syndrome. Total testosterone levels may be normal or mildly elevated and uncommonly above 200 ng/dL.

 

Monitoring of testosterone replacement therapy:

The efficacy of testosterone replacement in females is under study. If it is used, total testosterone levels should be kept within the normal female range at all times. Bioavailable or free testosterone levels also should be monitored to avoid over treatment.

 

Monitoring of antiandrogen therapy:

Antiandrogen therapy is most commonly employed in the management of mild-to-moderate "idiopathic" female hyperandrogenism, as seen in polycystic ovarian syndrome. Total testosterone levels are a relatively crude guideline for therapy and can be misleading. Therefore, bioavailable or free testosterone also should be monitored to ensure treatment adequacy. However, there are no universally agreed biochemical end points and the primary treatment end point is the clinical response.

 

See Steroid Pathways in Special Instructions.

 

Free testosterone:

Usually, bioavailable and free testosterone levels parallel the total testosterone levels. However, a number of conditions and medications are known to increase or decrease the sex hormone-binding globulin (SHBG) (SHBG / Sex Hormone Binding Globulin [SHBG], Serum) concentration, which may cause total testosterone concentration to change without necessarily influencing the bioavailable or free testosterone concentration, or vice versa:

-Treatment with corticosteroids and sex steroids (particularly oral conjugated estrogen) can result in changes in SHBG levels and availability of sex-steroid binding sites on SHBG. This may make diagnosis of subtle testosterone abnormalities difficult.

-Inherited abnormalities in SHBG binding

-Liver disease and severe systemic illness

-In pubertal boys and adult men, mild decreases of total testosterone without LH abnormalities can be associated with delayed puberty or mild hypogonadism. In this case, either bioavailable or free testosterone measurements are better indicators of mild hypogonadism than determination of total testosterone levels.

-In polycystic ovarian syndrome and related conditions, there is often significant insulin resistance, which is associated with low SHBG levels. Consequently, bioavailable or free testosterone levels may be more significantly elevated.

 

Either bioavailable (TTBS / Testosterone, Total and Bioavailable, Serum) or free testosterone (this test) should be used as supplemental tests to total testosterone in the above situations. The correlation coefficient between bioavailable and free testosterone (by equilibrium dialysis) is 0.9606. However, bioavailable testosterone is usually the preferred test, as it more closely reflects total bioactive testosterone, particularly in older men. Older men not only have elevated SHBG levels, but albumin levels also may vary due to coexisting illnesses.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Early-morning testosterone levels in young male individuals are, on average, 50% higher than p.m. levels. Reference values were established using specimens collected in the morning.

 

Testosterone levels can fluctuate substantially between different days, and sometimes even more rapidly. Assessment of androgen status should be based on more than a single measurement.

 

The low end of the normal reference range for total testosterone in prepubertal subjects is not yet established.

 

While free testosterone can be used for the same indications as bioavailable testosterone, determination of bioavailable testosterone levels may be superior to free testosterone measurement in most situations.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Manni A, Pardridge WM, Cefalu W, et al: Bioavailability of albumin-bound testosterone. J Clin Endocrinol Metab. 1985 Oct;61(4):705-10

2. New MI, Josso N: Disorders of gonadal differentiation and congenital adrenal hyperplasia. Endocrinol Metab Clin North Am. 1988 Jun;17(2):339-366

3. Morley JE, Perry HM III: Androgen deficiency in aging men: Role of testosterone replacement therapy. J Lab Clin Med. 2000 May;135(5):370-378

4. Sizonenko PC, Paunier L: Hormonal changes in puberty III: Correlation of plasma dehydroepiandrosterone, testosterone, FSH and LH with stages of puberty and bone age in normal boys and girls and in patients with Addison's disease or hypogonadism or with premature or late adrenarche. J Clin Endocrinol Metab. 1975 Nov;41(5):894-904

5. Goudas VT, Dumesic DA: Polycystic ovary syndrome. Endocrinol Metab Clin North Am. 1997 Dec;26(4):893-912

6. Braunstein GD: Androgen insufficiency in women: Summary of critical issues. Fertil Steril. 2002 Apr;77 Suppl 4:S94-99

7. Juul A, Skakkebaek NE: Androgens and the aging male. Hum Reprod Update. 2002 Sep-Oct;8(5):423-433

8. Hackbarth JS, Hoyne JB, Grebe SK, Singh RJ: Accuracy of calculated free testosterone differs between equations and depends on gender and SHBG concentration. Steroids. 2011 Jan;76(1-2):48-55

9. Goldman AL, Bhasin S, Wu FCW, et al: A reappraisal of testosterone’s binding in circulation: Physiological and clinical implications. Endocr Rev. 2017 Aug;38(4):302-324

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Method Description
Describes how the test is performed and provides a method-specific reference

Free Testosterone:

This method is based on equilibrium dialysis in which free-labeled testosterone is allowed to pass through a semipermeable membrane, whereas testosterone bound to the sex hormone-binding globulin (SHBG) remains inside the dialysis tubing. After dialysis, radioactivity is measured both inside and outside the tubing; the free testosterone results are expressed as a percentage of total testosterone. The resulting percentage is multiplied by the total testosterone concentration obtained by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and an absolute free testosterone value is obtained.(Vermeulen A, Stoica T, Verdonck L: The apparent free testosterone concentration, an index of androgenicity. J Clin Endocrinol Metab. 1971;33:759-767; Bammann BL, Coulam C, Jiang NS: Total and free testosterone during pregnancy. Am J Obstet Gynecol. 1980;137:293-298)

 

Total Testosterone:

Deuterated stable isotope (d3-testosterone) is added to a 0.2-mL serum sample as an internal standard. Protein is precipitated from the mixture by the addition of acetonitrile. The testosterone and internal standard are extracted from the resulting supernatant by an online extraction utilizing high-throughput liquid chromatography (HTLC). This is followed by conventional liquid chromatography and analysis on a tandem mass spectrometer equipped with a heated nebulizer ion source.(Wang C, Catlin DH, Demers LM, et al: Measurement of total testosterone in adult men: comparison of current laboratory methods versus liquid chromatography-tandem mass spectrometry. J Clin Endocrinol Metab. 2004;89:534-543; Taieb J, Mathian B, Millot F, et al: Testosterone measured by 10 immunoassays and by isotope-dilution gas chromatography-mass spectrometry in sera from 116 men, women, and children. Clin Chem. 2003;49:1381-1395)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Sunday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

3 to 5 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

See Individual Unit Codes

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

84402

84403

 

LOINC® Information

Test Id Test Order Name Order LOINC Value
TGRP Testosterone, Total and Free, S 58952-3
Result Id Test Result Name Result LOINC Value
Result LOINC Value Tooltip

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports