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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 *

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

 

"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

Clinical Significance:
Dehydroepiandrosterone is a 17-Ketosteroid produced primarily by the adrenal gland by side chain cleavage of 17-HydroxyPregnenolone.  It is reversibly converted to Dehydroepiandrosterone-Sulfate and Androstenediol.  It is also converted to Androstenedione.  It is excreted in the urine as Sulfate and Glucuronide conjugates and unconjugated (Free) forms.  DHEA is a weak androgen strongly bound to Sex Steroid Binding Globulin and weakly bound to Corticosteroid Binding Globulin and Albumin.  A small percentage of the total DHEA is not bound to any proteins and is the active moiety. DHEA is one of the first androgens to increase significantly at the onset on adrenarche.  Levels increase throughout puberty until adulthood.  In females, levels drop off sharply after menopause.  Free DHEA levels respond with greater sensitivity to stimulation and suppression challenges and readily demonstrate alterations in normal adrenal production. Free DHEA may distinguish adrenal causes of overandrogenization from gonadal causes.

Reference Ranges:
Male:                                      2.0 – 8.0 ng/dl
Female:
  Premenopausal:                             3.0 - 13 ng/dl
  Postmenopausal:                         2.0 – 8.0 ng/dl

Procedure:
Free Dehydroepiandrosterone is measured by radioimmunoassay.

Patient Preparation:
Patient should not be on any Steroid, 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.  Minimum specimen size is 1 ml.

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

Shipping Instructions:
Ship specimens frozen in dry ice.

References:
1. Swinkels LMJW, Ross HA, Smals AGH, and Benraad ThJ. Concentrations of Total and Free Dehydroepiandrosterone in Plasma and Dehydroepiandrosterone in Saliva of Normal and Hirsute Women under Basal Conditions and during Administration of Dexamethasone/Synthetic Cortictropin.  Clin Chem 36: 2042-2046, 1990.

2. Carmina E, Levin JH, Malizia G, and Lobo RA. Ovine Corticotropin-Releasing Factor and Dexamethasone Responses in Hyperandrogenic Women.  Fertil  Steril 54: 245-250, 1990.

CPT Code: 
Free DHEA 83519 and DHEA 82626

 

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

Clinical Significance:
Dehydroepiandrosterone is a 17-Ketosteroid produced primarily by the adrenal gland by side chain cleavage of 17-HydroxyPregnenolone.  It is reversibly converted to Dehydroepiandrosterone-Sulfate and Androstenediol.  It is also converted to Androstenedione.  It is excreted in the urine as Sulfate and Glucuronide conjugates and unconjugated (Free) forms.  This assay measures only the unconjugated for of DHEA present in the urine. Free DHEA urine is excreted into the urine primarily from Free (unbound) blood DHEA. DHEA urine is one of the first androgens to increase significantly at the onset of adrenache. Levels increase throughout puberty until adulthood.  In females, levels drop off sharply after menopause. DHEA may distinguish adrenal causes of overandrogenization from gonadal causes. Elevated levels of urine Free DHEA are found in third trimester pregnancies as DHEA becomes a direct precursor to Estrogen formulation. Free DHEA is excreted at a fairly constant rate throughout the day and gives a good integrated measurement of adrenal activity and function.

Reference Ranges:
Up to 1.1 mg/24 hours

Procedure:
Free Dehydroepiandrosterone is measured by radioimmunoassay.

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

Specimen Collection:
5ml of a 24 hour urine collection should be submitted. DO NOT ACIDIFY URINE. No special preservatives are required.  Minimum specimen size is 1 ml. Note 24 hour volume on request slip.

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

Shipping Instructions:
Ship specimens frozen in dry ice.

References:
1. Parker LH, O’Dell W. Decline of adrenal androgen production as measured by radioimmunoassay of urinary unconjugated dehydroepiandrosterone. J Clin Oncol & Metab 47: 600, 1978.

2. Carmina E, Levin JH, Malizia G and Lobo RA. Ovine corticotroin releasing factor and dexamethasone responses in hyperandrogenic women. Fertil Steril 54: 245-250, 1990.

CPT Code: 
Free DHEA 83519 and DHEA 82626

 

"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 *

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

 

"Free" Testosterone, urine *

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

 

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