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