17-alpha-Hydroxyprogesterone, serum
Clinical Background:
17-α-hydroxyprogesterone (17OHP) is a biosynthetic precursor of cortisol and thus of adrenal origin in males and females. In females there is an additional, though small, contribution from the ovar...
17-α-hydroxyprogesterone (17OHP) is a biosynthetic precursor of cortisol and thus of adrenal origin in males and females. In females there is an additional, though small, contribution from the ovary. Furthermore the amount of 17OHP secreted by the ovary varies throughout the menstrual cycle. Blood levels are higher in the luteal phase than in the follicular phase. Serum levels of 17OHP are raised when there is impairment in the 21- and 11a-hydroxylation steps through to cortisol. Diagnosis of classical congenital adrenal hyperplasia (CCAH) due to these defects (most commonly 21-hydroxylase deficiency) may be made by measuring 17OHP levels in serum/plasma. 17OHP levels may also be used to monitor glucocorticoid therapy in patients with CCAH. Newborns with CCAH may present with ambiguous genitalia (in females) or salt-wasting adrenal crisis, typically 2-3 weeks after birth. These adrenal crises are life-threatening.
Milder defects in 21-hydroxylase may lead to non-classcial CAH (NCCAH), also known as late-onset CAH. Female patients with NCCAH may present with a PCOS-like phenotype, with hirsuitism and/or menstrual irregularities. NCCAH may also be associated with early puberty.
Test Details
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Discipline:
Biochemistry
Biochemistry
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Specimen Container Adult:
Serum or EDTA plasma
Serum or EDTA plasma
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Specimen Container Paediatric:
Serum or EDTA plasma
Serum or EDTA plasma
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Minimum Volume Adult:
1 mL blood
1 mL blood
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Minimum Volume Paediatric:
1 mL blood
1 mL blood
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Special Requirement:
Special Requirement: Ideally do not collect before 3 days of age. For diagnosis in neonates, samples should be taken prior to any steroid replacement.
Special Requirement: Ideally do not collect before 3 days of age. For diagnosis in neonates, samples should be taken prior to any steroid replacement.
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Sample Stability:
Unseparated: Same day
Separated: 5 days at 4-8°C, 1 year at -20°C
Unseparated: Same day
Separated: 5 days at 4-8°C, 1 year at -20°C
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Transport Requirements:
Ambient
Ambient
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Interpretation:
Untreated individuals with CCAH due to 21-hydroxylase deficiency have very high serum/plasma 17OHP concentrations (usually >100 nmol/L). Androstenedione is also highly elevated. Non-specific elevat...
Read MoreUntreated individuals with CCAH due to 21-hydroxylase deficiency have very high serum/plasma 17OHP concentrations (usually >100 nmol/L). Androstenedione is also highly elevated. Non-specific elevations in 17OHP can occur in neonates due to prematurity, low birth weight, or stress.
In NCCAH 17OHP concentrations may be elevated (usually <100 nmol/L), but are within the reference range in some cases. Measurement of 17OHP after synacthen stimulation is therefore required in some cases to exclude or diagnose NCCAH. An exaggerated increase in 17OHP concentrations in response to synacthen is observed in NCCAH. -
Reference Ranges:
17-hydroxyprogesterone LC-MS/MS Reference Ranges (nmol/L):
Age
Male
Female
< 1yr
<7.5
<7.5
1-9
<3
<3
10+
<6.2
<6.8
17-hydroxyprogesterone LC-MS/MS Reference Ranges (nmol/L):
Age
Male
Female
< 1yr
<7.5
<7.5
1-9
<3
<3
10+
<6.2
<6.8
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Factors Affecting Result:
Prematurity, acute illness/stress may increase 17OHP in infants.
Prematurity, acute illness/stress may increase 17OHP in infants.
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Routine Contact Name:
Duty Biochemist
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Routine Telephone:
Freeman: 0191 244 8889
RVI: 0191 282 9719
Freeman: 0191 244 8889
RVI: 0191 282 9719
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Routine Email:
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Specialist Test:
Yes
Yes
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Specialist Contact Name:
Endocrine Lab
Endocrine Lab
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Specialist Telephone:
0191 282 4025
0191 282 4025