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Fibronectin*

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

 

Follicle Stimulating Hormone*
(FSH)

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

 

Follicle Stimulating Hormone (FSH), urine*

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

 

"Free" Aldosterone, urine *

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

 

"Free and Weakly Bound" Estradiol

Clinical Significance:
Estradiol is one of the three main Estrogens derived from metabolism of Testosterone and also converted reversibly to Estrone.  Estradiol is produced by ovarian follicles.  Estradiol is the most biologically potent of the Estrogens.  Estradiol is excreted into the urine in several different conjugated forms and also as unconjugated Estradiol. Estradiol is bound strongly to Estrogen Binding Globulin but is also present in the "free" (unbound) form or loosely bound to Albumin.  Estradiol in the "Free and Weakly Bound" form has bioavailable activity because it may readily be released in the "Free" bioactive form.  Factors that influence Estrogen Binding Globulin have a dramatic effect on "Free and Weakly Bound" Estradiol levels.  Patients on Estrogen Replacement therapy may have greatly elevated Estrogen Binding Globulin levels leading to very high total Estradiol levels but without the correlating elevation in "Free and Weakly Bound" Estradiol levels and Estrogenic activity.  Thyroid medication, contraceptives and Estrogens decrease the percent of "Free and Weakly Bound" Estradiol shielding the true Estrogenic level of activity from total Estradiol determinations.

Reference Ranges:
Male:                                   Up  to  0.22 pg/ml  
Female:
  Follicular:                             0.20 - 0.54 pg/ml
  Luteal:                                 0.20 - 1.20 pg/ml
  Menopausal:                         0.05 - 0.18 pg/ml

Procedure:
"Free and Weakly Bound" Estradiol is measured by a radioimmunodisplacement assay and a radioimmunoassay following extraction of specimens.

Patient requirements:
Patient should not be on any Steroid, ACTH, Gonadotropin or Estrogen medications, if possible, for at least 48 hours prior to collection of specimen.  Oral contraceptives and estrogen replacement therapy may influence "Free" Estradiol levels.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Minimum specimen size is 1.5 ml.

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

References:
1. N Mounib, Ch Sultan, J Bringer, B Hedon, JC Nicolas, P Cristol, N Bressot, and B Descomps.  Correlations between Free Plasma Estradiol and Estrogens Determined by Bioluminescence in Saliva, Plasma, and Urine during Spontaneous and FSH Stimulated Cycles in Women.  Journal of Steroid Biochemistry 31: 861-865, 1988.
 
2. MJ Reed, RW Cheng, CT Noel, HAF Dudley, and VHT James.  Plasma Levels of Estrone, Estrone Sulfate, and Estradiol and the Percentage of Unbound Estradiol in Postmenopausal Women with and without Breast Disease.  Cancer Research 43: 3940-3943, 1983.

 

"Free and Weakly Bound" 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 unbound (Free) form.  The "Free and Weakly Bound" Testosterone is the Bioavailable moiety of Testosterone.  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 genetalia, growth of facial hair and pubic hair.  Increased levels of "Free and Weakly Bound" 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.

Reference Ranges:
Male:                       105   -    390 ng/dl
Female:                     2.0  -   12.0 ng/dl

Procedure:
"Free and Weakly Bound" Testosterone is measured by radioimmunoassay following extraction of specimens and by radiodisplacement assay. 

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.

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

References:
1. LMJW Swinkels, HJC van Hoof, HA Ross, AGH Smals, and ThJ Benraad.  Concentrations of Salivary Testosterone and Plasma Total, Non-Sex-Hormone-Binding Globulin-Bound, and Free Testosterone in Normal and Hirsute Women during Administration of Dexamethasone/Synthetic Corticotropin.  Clinical Chemistry 37: 180 - 185, 1991.

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.

 

"Free" Cortisol *

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

 

"Free" Cortisol, urine *

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

 

"Free" Cortisone*

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

 

"Free" Dehydroepiandrosterone*
"Free" DHEA

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

 

"Free" Dehydroepiandrosterone
("Free" DHEA), urine*

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

 

"Free" Dihydrotestosterone
"Free" DHT

Clinical Significance:
Dihydrotestosterone is an extremely potent androgen produced primarily from gonadal and peripheral conversion of Testosterone.  Dihydrotestosterone is reversibly converted to 3a-Androstanediol.   Dihydrotestosterone is excreted into the urine directly and as part of the 17-ketosteroids.  Dihydrotestosterone is produced in the Leydig cells and germinal tissue, in addition to conversion by skin.  Dihydrotestosterone is extensively bound to Sex-Steroid Binding Globulin and to Albumin.  Only a small percentage is in the "free" form.   "Free" Dihydrotestosterone is the active moiety.  "Free"  Dihydrotestosterone exerts all of the biological actions attributed to Dihydrotestosterone, but has a greater sensitivty and exhibits greater specificity in gonadal dysfunction.  "Free" Dihydrotestosterone is involved in many of the clinical manifestations presented in gonadal disorders.  Hirsute females have increased greatly increased "Free" Dihydrotestosterone levels due to increased 5a-reductase levels in the skin.  Males with 5a-reductase deficiencies often have elevated or normal Testosterone levels, but very low or non-detectable levels of "Free" Dihydrotestosterone. 

Reference Ranges:
Male:                            5.0 - 15.0 pg/ml
Female:                        0.3 -   2.2 pg/ml

Procedure:
"Free" Dihydrotestosterone is measured by radioimmunoassay following extraction and purification of the specimens.

Patient Preparation:
Patient should not be on any ACTH, Steroid, Gonadotropin, or Estrogen 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 1.5 ml.

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

References:
1. V Toscano and R Horton.  Circulating DHT May not Reflect Peripheral Formation.  Journal of Clinical Investigations 79: 1763, 1987.

2. HJ Horst, W Bartsch, and I Dirksen-Thedens.  Plasma Testosterone, Sex Hormone Binding Globulin Capacity and Per Cent Binding of Testosterone and 5a-Dihydrotestosterone in Prepubertal, Pubertal and Adult Males.  Journal of Clinical Endocrinology and Metabolism 45: 522, 1977.

 

"Free" Estradiol (f E2)

Clinical Significance:
Estradiol is one of the three main Estrogens derived from metabolism of Testosterone and also converted reversibly to Estrone.  Estradiol is produced by ovarian follicles.  Estradiol is the most biologically potent of the Estrogens.  Estradiol is excreted into the urine in several different conjugated forms and also as unconjugated Estradiol. Estradiol is bound strongly to Estrogen Binding Globulin but is also present in the "free" (unbound) form or loosely bound to Albumin.   Only Estradiol in the "Free" form has biological activity.  Factors that influence Estrogen Binding Globulin have a dramatic effect on "Free" Estradiol levels.  Patients on Estrogen Replacement therapy may have greatly elevated Estrogen Binding Globulin levels leading to very high total Estradiol levels but without the correlating elevation in "Free" Estradiol levels and Estrogenic activity.  Thyroid medication, contraceptives and Estrogens decrease the percent of "Free" Estradiol shielding the true Estrogenic level of activity from total Estradiol determinations.

Reference Ranges:
Male:                                      0.2 – 0.5  pg/ml
Female:
  Follicular:                             0.34 - 1.26 pg/ml
  Luteal:                                 0.80 - 3.45 pg/ml
  Menopausal:                         0.12 - 0.39 pg/ml

Procedure:
"Free" Estradiol is measured by a radioimmunodisplacement assay and a radioimmunoassay following extraction of specimens.

Patient requirements:
Patient should not be on any Steroid, ACTH, Gonadotropin or Estrogen medications, if possible, for at least 48 hours prior to collection of specimen.  Oral contraceptives and estrogen replacement therapy may influence "Free" Estradiol levels.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Minimum specimen size is 1.5 ml.

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

References:
1. N Mounib, Ch Sultan, J Bringer, B Hedon, JC Nicolas, P Cristol, N Bressot, and B Descomps.  Correlations between Free Plasma Estradiol and Estrogens Determined by Bioluminescence in Saliva, Plasma, and Urine during Spontaneous and FSH Stimulated Cycles in Women.  Journal of Steroid Biochemistry 31: 861-865, 1988.
 
2. MJ Reed, RW Cheng, CT Noel, HAF Dudley, and VHT James.  Plasma Levels of Estrone, Estrone Sulfate, and Estradiol and the Percentage of Unbound Estradiol in Postmenopausal Women with and without Breast Disease.  Cancer Research 43: 3940-3943, 1983.

 

"Free" Insulin*

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

 

"Free" Progesterone

Clinical Significance:
Progesterone is a Progestin produced primarily from enzymatic metabolism of Pregnenolone.  It is enzymatically converted to 17-Hydroxy Progestrone and 11-Deoxycorticosterone.  It is secreted by both the gonads and the adrenal glands.  It is mostly bound to Cortisol Binding Globulin and Albumin, but a small percentage is present in the "Free" form.  This "Free" Progesterone is the bioactive moiety.  It is excreted into the urine primarily as "Free" unconjugated Progesterone and as Pregnanediol. Progesterone is responsible for cellular changes in the cervix, vagina, and uterus.  Levels are lowest in the follicular phase and increase rapidly following the luteal surge.  Increased Progesterone inhibits ovulation.  "Free" Progesterone increases greatly during pregnancy reaching about 20% of the total Progesterone concentration at delivery.  Measurement of Progesterone can be useful to monitor fertility, corpus luteum function, endometrial development, and be helpful in in-vitro fertilization patients.

Reference Ranges:
Male:                               Up  to  50 ng/dl
Female:                           Up  to  50 ng/dl
Pregnancy:                       50 - 2000 ng/dl

Procedure:
"Free" Progesterone is measured by radioimmunoassay following ultrafiltration of specimens.

Patient Preparation:
Patient should not be on any Corticosteroid, ACTH, Estrogen, or Gonadotropin medication, 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.

Shipping Instructions:
Ship specimens frozen in dry ice.

References:
1. S Batra, LP Bengtsson, H Grundsell, and N-O Sjoberg.  Levels of Free and Protein-Bound Progesterone in Plasma during Late Pregnancy.  Journal of Clinical Endocrinology and Metabolism 42:  1041, 1976.

2. CJ Munro, GH Stabenfeldt, JR Cragun, LA Addiego, JW Overstreet, and BL Lasley.  Relationship of Serum Estradiol and Progesterone Concentrations to the Excretion Profiles of Their Major Urinary Metabolites as Measured by Enzyme Immunoassay and Radioimmunoassay.  Clinical Chemistry 37: 38-44, 1991.

 

"Free" Progesterone, urine

Clinical Significance:
Progesterone is a Progestin produced primarily from enzymatic metabolism of Pregnenolone.  It is enzymatically converted to 17-Hydroxy Progestrone and 11-Deoxycorticosterone.  It is secreted by both the gonads and the adrenal glands.  It is bound to Cortisol Binding Globulin and Albumin, but a small percentage is present in the "Free" bioactive form.  It is excreted into the urine as its conjugated and "Free" unconjugated forms and as Pregnanediol (conjugated and unconjugated).  This assay measures only the "Free" unconjugated form of Progesterone. Urinary "Free" Progesterone levels parallel blood levels offering a non-invasive method of specimen collection. Progesterone is responsible for cellular changes in the cervix, vagina, and uterus.  Levels are lowest in the follicular phase and increase rapidly following the luteal surge.  Progesterone increases greatly during pregnancy.  Measurement of Urinary "Free" Progesterone can be useful to monitor fertility, corpus luteum function, endometrial development, and be helpful in in-vitro fertilization patients yielding an integrated look of Progesterone activity over a 24 hour period.

Reference Ranges:
Male:                      Up to 0.2 ug/24 hours
Female:
  Follicular:              Up to 0.2 ug/24 hours
  Luteal:                   0.4 -  2.5 ug/24 hours

Procedure:
Urinary "Free" Progesterone is measured by radioimmunoassay following extraction of specimens.

Patient Preparation:
Patient should not be on any Corticosteroid, ACTH, Estrogen, or Gonadotropin medication, 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:
2. HJ van der Molem and C Corpechot.  Isolation and Identification of Progesterone from Urine of Nonpregnant Women.  Journal of Clinical Endocrinology and Metabolism  28: 1361, 1968.

2. CJ Munro, GH Stabenfeldt, JR Cragun, LA Addiego, JW Overstreet, and BL Lasley.  Relationship of Serum Estradiol and Progesterone Concentrations to the Excretion Profiles of Their Major Urinary Metabolites as Measured by Enzyme Immunoassay and Radioimmunoassay.  Clinical Chemistry 37: 38-44, 1991.

 

"Free" 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 unbound (Free) form.  The "Free" Testosterone is the Bioactive moiety of Testosterone.  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 "Free" 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.

Reference Ranges:
Male:                       5.5   -   20.0 ng/dl
Female:                    0.20 -   0.72 ng/dl

Procedure:
"Free" Testosterone is measured by radioimmunoassay following the 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 should be collected and separated as soon as possible.  Minimum specimen size is 1 ml.

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

References:
1. LMJW Swinkels, HJC van Hoof, HA Ross, AGH Smals, and ThJ Benraad.  Concentrations of Salivary Testosterone and Plasma Total, Non-Sex-Hormone-Binding Globulin-Bound, and Free Testosterone in Normal and Hirsute Women during Administration of Dexamethasone/Synthetic Corticotropin.  Clinical Chemistry 37: 180 - 185, 1991.

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.

 

"Free" 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 only the "Free" unconjugated 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 of Urine "Free" 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 "Free" Testosterone measurement gives an accurate picture of Testosterone production integrated ovar a 24 hour period.

Reference Ranges:
Male:                         3.0   -  12 ug/24 hours
Female:                      Up to 2.0 ug/24 hours

Procedure:
Urine "Free" 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:
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.

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