Pregnenolone - Quest Diagnostics · large amounts of DHEA-sulfate and pregnenolone. Pregnenolone...
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Alphabetical Test Section 139 Clinical Use • Diagnose 3β-hydroxysteroid dehydrogenase deficiency • Diagnose adrenal virilizing tumors Related Assays • 17-Hydroxypregnenolone • DHEA • DHEA-sulfate Reference Range Interpretive Information • Congenital adrenal hyperplasia • Adrenal virilizing tumor • Cushing’s disease • Normal children and adults after ACTH administration Clinical Background Normal steroid-producing cells of the adrenal glands and gonads synthesize various steroids from circulating cholesterol ester. This results in small amounts of precursors such as pregnenolone, a 5 C-21 steroid, leaking into the circulation. Most of the circulating pregnenolone is from the adrenal cortex, and levels are modestly increased after ACTH administration in normal children and adults. This assay is useful in diagnosing 3β-hydroxysteroid dehydrogenase (3β-HSD) deficiency, an unusual form of congenital adrenal hyperplasia associated with blocked cortisol synthesis and increased levels of 5 steroids. After diagnosis of 3β-HSD deficiency, the test can evaluate gluco- corticoid replacement therapy. The assay is also helpful in suggesting the presence of an adrenal virilizing tumor, since almost all of these tumors secrete large amounts of DHEA-sulfate and pregnenolone. Pregnenolone levels are moderately increased in Cushing’s disease due to ACTH-secreting pituitary adenoma or ectopic causes. Method • Extraction, chromatography, radioimmunoassay (RIA) • Analytical sensitivity: 10 ng/dL Specimen Requirements 4 mL refrigerated serum 1.1 mL minimum No additive red top preferred SST red top acceptable ng/dL ng/dL Men 10-200 Women 10-230 Children ACTH stimulation Baseline 60 min <1 y 10-140 49-360 1-5 y 10-48 34-135 6-12 y 15-45 39-105 Tanner II-III Males 10-45 58-110 Females 15-84 33-140 Tanner IV-V Males 11-50 37-150 Females 20-77 91-220 Pediatric data from J Clin Endocrinol Metab. 1992;75:1491-1496. Pregnenolone 31493X
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Transcript of Pregnenolone - Quest Diagnostics · large amounts of DHEA-sulfate and pregnenolone. Pregnenolone...
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139
Clinical Use
• Diagnose 3β-hydroxysteroid dehydrogenase deficiency
• Diagnose adrenal virilizing tumors
Related Assays• 17-Hydroxypregnenolone• DHEA• DHEA-sulfate
Reference Range
Interpretive Information
• Congenital adrenal hyperplasia• Adrenal virilizing tumor• Cushing’s disease• Normal children and adults
after ACTH administration
Clinical Background
Normal steroid-producing cells of the adrenal glands and gonads synthesize various steroids from circulating cholesterol ester. This results in small amounts of precursors such as pregnenolone, a 5 C-21 steroid, leaking into the circulation. Most of the circulating pregnenolone is from the adrenal cortex, and levels are modestly increased after ACTH administration in normal children and adults.This assay is useful in diagnosing 3β-hydroxysteroid dehydrogenase (3β-HSD) deficiency, an unusual form of congenital adrenal hyperplasia associated with blocked cortisol synthesis and increased levels of 5 steroids. After diagnosis of 3β-HSD deficiency, the test can evaluate gluco-corticoid replacement therapy. The assay is also helpful in suggesting the presence of an adrenal virilizing tumor, since almost all of these tumors secrete large amounts of DHEA-sulfate and pregnenolone.Pregnenolone levels are moderately increased in Cushing’s disease due to ACTH-secreting pituitary adenoma or ectopic causes.
Method
• Extraction, chromatography, radioimmunoassay (RIA)
• Analytical sensitivity: 10 ng/dL
Specimen Requirements
4 mL refrigerated serum1.1 mL minimum
No additive red top preferredSST red top acceptable
ng/dL ng/dLMen 10-200Women 10-230Children
ACTH stimulation Baseline 60 min<1 y 10-140 49-3601-5 y 10-48 34-1356-12 y 15-45 39-105Tanner II-III
Males 10-45 58-110Females 15-84 33-140
Tanner IV-VMales 11-50 37-150Females 20-77 91-220
Pediatric data from J Clin Endocrinol Metab. 1992;75:1491-1496.
Pregnenolone 31493X
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