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:                                      0.7 – 12.5 ng/dl
Female:
  Premenopausal:                   0.8 – 15.0 ng/ml
  Postmenopausal:                 0.7 – 12.0 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