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Testosterone

Clinical Significance:
Testosterone is a potent androgen produced primarily by metabolism of Androstenedione and Androstenediol.  It is converted to Estradiol, Dihydrotestosterone, Androsterone, and Etiocholanolone.  It is excreted into the urine as conjugated and unconjugated (Free) forms of Testosterone and also is responsible for much of the 17-Ketosteroids found in the urine.  Testosterone is strongly bound to Testosterone Binding Protein, weakly bound to Albumin and also present in the bioactive unbound (Free) form.  In males the vast majority of Testosterone is produced by the Leydig cells under the control of Luteinizing Hormone.  In females, most of the Testosterone is of adrenal origin.  Testosterone is responsible for development of secondary sex characteristics including external genitalia, growth of facial hair and pubic hair.  Increased levels are found in patients with Polycystic Ovarian Disease, Hirsutism, Ovarian Tumors, Arrhenoblastomas, Hilus Cell Tumors, Adrenal Hyperplasia and Adrenal Tumors.  Decreased levels are found in Hypogonadism, Klinefelter's Syndrome, Hypopituitarism, and Estrogen Therapy.

Reference Ranges:
Male:                          450 - 1000 ng/dl
Female:                      20 -      54 ng/dl

Procedure:
Testosterone is measured by radioimmunoassay following extraction of specimens. 

Patient Preparation:
Patient should not be on any Steroid, Thyroid, ACTH, Estrogen or Gonadotropin medications, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Minimum specimen size is 1 ml.

Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:
Ship specimens at room temperature or frozen in dry ice.

References:
1. S Loric, J Guechot, F Duron, P Aubert, and J Giboudeau.  Determination of Testosterone in Serum Not Bound by Sex-Hormone-Binding Globulin:  Diagnostic Value in Hirsute Women.  Clinical Chemistry 34: 1826-1829, 1988.

2. TJ Wilke and David J Utley.  Total Testosterone, Free-Androgen Index, Calculated Free Testosterone, and Free Testosterone by Analog RIA Compared in Hirsute Women and in Otherwise-Normal Women with Altered Binding of Sex-Hormone-Binding Globulin.  Clinical Chemistry 33: 1372-1375, 1987.

 

Testosterone, Saliva*

* Test available on a research basis only. Contact ISI for details.

 

Testosterone, urine

Clinical Significance:
Testosterone is a potent androgen produced primarily by metabolism of Androstenedione and Androstenediol.  It is converted to Estradiol, Dihydrotestosterone, Androsterone, and Etiocholanolone.  It is excreted into the urine as conjugated and unconjugated (Free) forms of Testosterone and also is responsible for much of the 17-Ketosteroids found in the urine.  This assay measures the total of the conjugated and unconjugated forms.  In males the vast majority of Testosterone is produced by the Leydig cells under the control of Luteinizing Hormone.  In females, most of the Testosterone is of adrenal origin.  Testosterone is responsible for development of secondary sex characteristics including external genitalia, growth of facial hair and pubic hair.  Increased levels of Urine Testosterone are found in patients with Polycystic Ovarian Disease, Hirsutism, Ovarian Tumors, Arrhenoblastomas, Hilus Cell Tumors, Adrenal Hyperplasia and Adrenal Tumors.  Decreased levels are found in Hypogonadism, Klinefelter's Syndrome, Hypopituitarism, and Estrogen Therapy.  Urine Testosterone measurement gives an accurate picture of Testosterone production integrated ovar a 24 hour period.

Reference Ranges:
Male:                           40  - 120 ug/24 hours
Female:                       2.0 -   10 ug/24 hours

Procedure:
Urine Testosterone is measured by radioimmunoassay following hydrolysis and extraction of specimens. 

Patient Preparation:
Patient should not be on any Steroid, Thyroid, ACTH, Estrogen or Gonadotropin medications, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
10 ml of a 24 hour urine collection should be submitted for analysis. No special preservatives are required. Store specimen refrigerated during collection. Specimens should be frozen prior to shipping. Minimum specimen size is 5 ml.

Shipping Instructions:
Ship specimens frozen in dry ice. Provide the total volume per 24 hours.

References:
1. Y Doberne and MI New.  Urinary Androstanediol and Testosterone in Adults.  Journal of Clinical Endocrinology and Metabolism 42: 152, 1976.

2. TJ Wilke and David J Utley.  Total Testosterone, Free-Androgen Index, Calculated Free Testosterone, and Free Testosterone by Analog RIA Compared in Hirsute Women and in Otherwise-Normal Women with Altered Binding of Sex-Hormone-Binding Globulin.  Clinical Chemistry 33: 1372-1375, 1987.

 

Testosterone Binding Protein Index*
(TBP-I)

* Test available on a research basis only. Contact ISI for details.

 

Tetrahydroaldosterone
(TH-Aldo), urine*

* Test will be discontinued as of July 1, 2013 and specimens will not be accepted after June 15th, 2013. Contact ISI for details.

 

Tetrahydrocorticosterone (THB), (Urine)*

* Test available on a research basis only. Contact ISI for details.

 

Tetrahydrocorticosterone, Allo (allo-THB), (Urine)*

* Test available on a research basis only. Contact ISI for details.

 

Tetrahydrocortisol
(TH-F), urine*

* Test will be discontinued as of July 1, 2013 and specimens will not be accepted after June 15th, 2013. Contact ISI for details.

 

Tetrahydrocortisol, Allo-
(Allo-TH-F), urine*

* Test will be discontinued as of July 1, 2013 and specimens will not be accepted after June 15th, 2013. Contact ISI for details.

 

Tetrahydrocortisone
(TH-E)*

* Test will be discontinued as of July 1, 2013 and specimens will not be accepted after June 15th, 2013. Contact ISI for details.

 

Tetrahydrocortisone, Allo-
(Allo-TH-E), urine*

* Test will be discontinued as of July 1, 2013 and specimens will not be accepted after June 15th, 2013. Contact ISI for details.

 

Tetrahydro
11-Dehydrocorticosterone
(TH-A), urine*

* Test available on a research basis only. Contact ISI for details.

 

Tetrahydro Deoxycorticosterone
(TH-DOC), urine *

* Test available on a research basis only. Contact ISI for details.

 

Tetrahydrodeoxycortisol
TH-S), urine*

* Test will be discontinued as of July 1, 2013 and specimens will not be accepted after June 15th, 2013. Contact ISI for details.

 

Tetrahydro-18-Hydroxy Corticosterone
(TH-18-OH-B), urine*

* Test available on a research basis only. Contact ISI for details.

 

Tetrahydro-18-Hydroxy Deoxycorticosterone
(TH-18-OH-DOC), urine*

* Test available on a research basis only. Contact ISI for details.

 

Thromboxane A2
(TxA2)*

* Test available on a research basis only. Contact ISI for details.

 

Thromboxane B2
(TxB2)*

* Test available on a research basis only. Contact ISI for details.

 

Thromboxane B2, urine*

* Test available on a research basis only. Contact ISI for details.

 

Thyrotropin Releasing Hormone (TRH)

Clinical Significance:
Thyrotropin Releasing Hormone (TRH) is a tripeptide produced primarily by the hypothalamus.  TRH is produced from a prohormone which contains multiple copies of the TRH molecule meaning that several TRH entities can be released from one precursor.  It has a stimulatory effect on the pituitary releasing Thyrotropin (TSH).  TRH secretion is controlled in a negative feedback system by thyroid hormones.  Binding of TRH to its receptor causes a rise in calcium which initiates TSH secretion.  It also stimulates adenyl cyclase in the pituitary.  TRH also stimulates secretion of Prolactin, Growth Hormone in Acromegaly, and ACTH in Cushing's and Nelson's Syndromes.  Levels of TRH are non-detectable or very low in patients with Hyperthyroidism and Hypothalamic Hypothyroidism.  Levels are elevated in patients with Primary and Pituitary Hypothyroidism

Reference Range:
Up to 40 pg/ml

Procedure:
Thyrotropin Releasing Hormone is measured by direct radioimmunoassay.

Patient Preparation:
Patient should not be on any thyroid medication, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
Collect 10mL blood in the special TRH preservative tube filling tube completely and separate as soon as possible. Freeze specimen immediately after separation. Minimum specimen size is 1 ml. Special TRH preservative tubes are available from Inter Science.

Important Precaution:
Thyrotropin Releasing Hormone must be collected with the TRH Preservative.  No other specimen is acceptable.

Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:
Ship specimens frozen in dry ice.

References:
1. MM Kaplan, JA Taft, S Reichlin, and TL Munsat.  Sustained Rises in Serum Thyrotropin, Thyroxine, and Triiodothyronine during Long Term, Continuous Thyroid Releasing Hormone Treatment in Patients with Amylotrophic Lateral Sclerosis.  Journal of Clinical Endocrinology and Metabolsim 63: 808, 1986.

2. GE Shambaugh III, JF Wilber, E Montoya, H Ruder, and ER Blonsky.  Thyrotropin-Releasing Hormone (TRH):  Measurement in Human Spinal Fluid.  Journal of Clinical Endocrinology and Metabolism 41: 131, 1975.

 

Thyrotropin Releasing Hormone (TRH), urine*

* Test available on a research basis only. Contact ISI for details.

 

Thyroxine*
(T4), urine*

* Test available on a research basis only. Contact ISI for details.

 

Triiodothyronine*
(T3), urine*

* Test available on a research basis only. Contact ISI for details.

 

Tumor Necrosis Factor Alpha

Clinical Significance:
Tumor Necrosis Factor Alpha is a 17,000 molecular weight peptide produced primarily from macrophages, fibroblasts and T cells. Tumor Necrosis Factor Alpha is also known as Cachectin. Tumor Necrosis Factor Alpha is a cytokine that is an important mediator in several inflammatory disorders including those affecting the central nervous system. It has also been shown to be capable of selectively damaging oligodendrocytes and myelin sheaths in vitro which may be relevant in disease progression in patients with multiple sclerosis. Tumor Necrosis Factor Alpha stimulates Collagenase Activity, and Prostaglandin E2 production by synovial cells. It also promotes angiogenesis, stimulation of platelet-activating activity in endothelial tissue, cytotoxicity on tumor cells, and stimulation of proliferation of normal fibroblasts. Levels are elevated by endotoxins, toxic shock protein, mycobacterial proteins, fungeal antigens, viruses and complement C5a. It stimulates and is stimulated by Interleukin 1, and is stimulated by Interferon Gamma.

Reference Range:
10 - 50 pg/ml

Procedure:
Tumor Necrosis Factor a is measured by direct radioimmunoassay.

Patient Preparation:
Patient should not be on any Corticosteroids, anti-inflammatory medications or pain killers, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Freeze specimen immediately after separation.  Minimum specimen size is 1 ml.

Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:
Ship specimens frozen in dry ice.

References:
1. MK Sharief, and R Hentges.  Association between Tumor Necrosis Factor-a and Disease Progression in Patients with Multiple Sclerosis.  New England Journal of Medicine 325: 467-472, 1991.

2. K Koike, K Hirota, M Ohmichi, K Kadowaki, H Ikegami, M Yamaguchi, A Miyake, and O Tanizawa.  Tumor Necrosis Factor-a Increases Release of Arachidonate and Prolactin from Rat Anterior Pituitary Cells.  Endocrinology 128: 2791-2798, 1991.

 

Tumor Necrosis Factor Beta (Beta-TNF)*

* Test available on a research basis only. Contact ISI for details.

 

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