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Lab Dept:
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Chemistry
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Test Name:
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DIHYDROTESTOSTERONE
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General Information
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Lab Order Codes:
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DHT
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Synonyms:
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DHT
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CPT Codes:
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82651 – Dihydrotestosterone (DHT)
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Test Includes:
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Dihydrotestosterone level reported in ng/mL.
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Logistics
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Test Indications:
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Serum DHT is an important steroid test for children, women and men because it is the immediate and active metabolite of testosterone. Conversion of testosterone to DHT occurs in target tissue by the action of 5a-reductase. Levels are normally low in children, but may be elevated in cases of steroid metabolic disease such as CAH (Congenital Adrenal Hyperplasia). Elevated levels in women may indicate ovarian disease. Low levels relative to testosterone may indicate partial or complete inactivity of 5a-reductase.
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Lab Testing Sections:
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Chemistry - Sendouts
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Referred to:
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Esoterix, Inc. (Test# 500144)
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Phone Numbers:
Minneapolis:
Saint Paul:
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612-813-6280
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651-220-6550
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Test Availability:
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Daily, 24 hours
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Turnaround Time:
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1-3 days, test is set up Tuesday through Saturday
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Special Instructions:
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N/A
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Specimen
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Specimen Type:
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Blood
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Container:
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Red top (plain, no gel) tube
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Draw Volume:
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3 mL (Minimum: 1.5 mL) blood
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Processed Volume:
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1 mL (Minimum: 0.5 mL) serum
Note: Submission of the minimum amount will not allow for repeat analysis.
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Collection:
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Routine venipuncture
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Special Processing:
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Lab Staff: Centrifuge specimen within one hour of draw. Remove serum aliquot into a screw-capped round bottom plastic vial. Store and ship at frozen temperatures. Forward promptly.
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Patient Preparation:
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None
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Sample Rejection:
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Mislabeled or unlabeled specimens
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Interpretive
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Reference Range:
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Premature Infants:
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Males:
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10 – 53 ng/dL
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Females:
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2 – 13 ng/dL
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Full Term Infants:
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Males:
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30 - 85 ng/dL
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Females:
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4 - 22 ng/dL
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Infants (2 weeks – 6 months):
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Males: DHT decreases rapidly the first week then increases to 12 – 85 ng/dL between 30 – 60 days. Levels then decrease gradually to prepubertal values by 7 months.
Females: Levels decrease during the first month to <3 ng/dL and remain there until puberty.
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Prepubertal Children:
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<3 ng/dL
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Puberty:
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Male
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Female
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Tanner Stage
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AGE (years)
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DHT ng/dL
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Age (year)
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DHT ng/dL
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1
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<9.8
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<3
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<9.2
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<3
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2
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9.8 – 14.5
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3 – 17
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9.2 – 13.7
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5 – 12
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3
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10.7 – 15.4
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8 – 33
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10.0 – 14.4
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7 – 19
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4
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11.8 – 16.2
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22 – 52
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10.7 – 15.6
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4 – 13
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5
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12.8 – 17.3
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24 – 65
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11.8 – 18.6
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3 – 18
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Adults:
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Males:
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30 – 85 ng/dL
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Females:
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4 – 22 ng/dL
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Critical Values:
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N/A
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Limitations:
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LLOQ (sensitivity) 1ng/dL
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Methodology:
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HPLC Tandem Mass Spectrometry
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References:
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Esoterix, Inc. “Expected Value & S.I. Unit Conversion Table” Fifth Edition, 2003
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Esoterix, Inc. Web Page July 2012
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Updates:
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8/3/2009: Note updated reference ranges.
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