Steroids

Aldosterone is produced in the zona glomerulosa of the adrenal glands in response to renin and angiotensin intermediates. Measurement of aldosterone is most useful in the investigation of hypertension when measured concurrently with renin so that an aldosterone/renin ratio may be calculated.

Beta blockers, diuretics, ACE inhibitors, angiotensin II receptor blockers, calcium channel blockers, a restricted salt diet and posture can affect interpretation of aldosterone results.

Sample Requirements and Reference Ranges

• Sample Type: Plasma
• Container: EDTA
• Precautions: Posture and relevant drug therapies (see above) may affect interpretation of results.
• Minimum Volume: 500 µL (140 µL for neonates)
• Reference Range:
  • <1 month: 140 – 4900 pmol/L
  • 1-12 months: 140 – 2500 pmol/L
  • 1 year – <2 years: 140 – 1500 pmol/L
  • 2 year – <5 years: 75 – 970 pmol/L
  • 5 years & above: 75 – 630 pmol/L

• Turnaround Time: 14 days
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: UK NEQAS

17-hydroxyprogesterone (17OHP) is one of the intermediary steroid metabolites in the cortisol biosynthetic pathway. The most common genetic defect in cortisol production is deficiency of the 21-hydroxlase enzyme, which leads to congenital adrenal hyperplasia (CAH). 17OHP concentrations are raised in this form of CAH (approximately 90% of CAH cases) and is a useful marker to monitor response to therapy. Measuring 17OHP in blood spot samples is less invasive than venepuncture and allows multiple samples to be taken over a 24hr period.

Blood spot 17OHP is not a diagnostic test and is only useful in monitoring treatment.

Sample Requirements and Reference Ranges

• Sample Type: Whole blood spotted onto pre-prepared card (available on request)
• Container: N/A
• Precautions: None
• Minimum Volume: Ensure that blood soaks through to the back of the card
• Reference Range: N/A
• Turnaround Time: 56 days
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: RfB

Dehydroepiandrosterone sulphate (DHEAS) is the sulphated ester of the 19-carbon androgen DHEA, produced by the adrenal gland. DHEAS is the most abundant circulating androgen and shows no diurnal rhythm. DHEAS acts as a precursor to other androgens, such as androstenedione and testosterone.

Measurement of DHEAS may be of benefit for the investigation of excess androgen. DHEAS is relatively specific for the adrenal glands, whereas other androgens, such as testosterone and androstenedione are also produced by the gonads.

Measurement of DHEAS is unhelpful in adult males.

Sample Requirements and Reference Ranges

• Sample Type: Serum or Plasma
• Container: SST or Lithium Heparin
• Precautions: None
• Minimum Volume: 500 μL (140 μL for neonates)
• Reference Range:
  • Pre-pubertal: <2.0 μmol/L
  • Adult female <50 yr: ≤9.6 μmol/L
  • Adult female  ≥50 yr: ≤3.1 μmol/L

• Turnaround Time: 14 days
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: UK NEQAS

Cortisol is an essential glucocorticoid steroid produced by the adrenal cortex. Cortisol circulates bound to cortisol binding protein (CBG) with only 15% being the unbound biologically active form. The saliva concentration generally reflects the free cortisol concentration in serum and may be useful in the investigation of cyclical Cushing’s syndrome due to the non-invasive nature of sample collection.

Sample Requirements and Reference Ranges

• Sample Type: Saliva (passive drool)
• Container: 5 mL plain (can be supplied by laboratory)
• Precautions: If multiple samples collected over several weeks, store frozen and send by 1st class post.
• Minimum Volume: 2.5 mL
• Reference Range:
  • am: <20 nmol/L
  • pm: <5 nmol/L

• Turnaround Time: 35 days
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: UKNEQAS

The serum androgen profile simultaneously measures:

• testosterone
• androstenedione
• 17-hydroxyprogesterone (17OHP)
• 11-deoxycortisol (11DOC)
• 21-deoxycortisol (21DOC)

11DOC and 21DOC are not routinely reported. If an abnormality is detected in either, a comment will be made on the report.

The androgen profile is recommended for investigation of hirsutism, polycystic ovarian syndrome (PCOS) and infertility in females, and for the diagnosis and monitoring of congenital adrenal hyperplasia (CAH) in both males and females. Please state clinical details and menstrual cycle information on the request form. 

Androgens pre- and 60-min post synacthen may be of benefit for the investigation of late onset CAH if elevated androgens have been observed in a follicular phase sample.

In neonates, 17OHP can be measured from the day of birth for the investigation of CAH, however levels may continue to rise immediately after birth, with further adrenal stimulation. An elevated 21DOC would confirm 21-hydroxylase deficiency CAH.

Sample Requirements and Reference Ranges

• Sample Type: Serum
• Container: SST. Please send primary sample if possible. Some interference has been observed with certain aliquoter tubes, such as the Impeco tube.
• Precautions: None
• Minimum Volume: 500 μL (140 μL for neonates)
• Reference Range:
  • Adult Females:
    • Testosterone <1.5 nmol/L
    • 17-Hydroxyprogesterone <6.0 nmo/L
    • Androstenedione (18 – 40yrs) <5.5 nmol/L
    • Androstenedione (>40yrs) <3.0 nmol/L
  • Adult Males:
    • Testosterone 7.0 – 30 nmol/L
    • 17-Hydroxyprogesterone <6.0 nmol/L
    • Androstenedione <5.5 nmol/L
  • Paediatric ranges under evaluation

• Turnaround Time: 7 days (Please contact the lab to notify of any urgent neonatal  sample)
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: UK NEQAS

Testosterone

Testosterone is a 19-carbon androgen, produced by both the adrenal glands and gonads. Production is controlled by LH or HCG. Serum testosterone is often measured in female patients to investigate suspected polycystic ovary syndrome (PCOS) or idiopathic hirsutism. However, some women will have a more serious pathology, such as adrenal/ovarian tumours, Cushing’s syndrome or late onset congenital adrenal hyperplasia (CAH).

In females, testosterone, androstenedione and 17-hydroxyprogesterone (17OHP) are lowest in the follicular phase. In males, testosterone is highest early in the morning and declines through the day.

Androstenedione

Androstenedione is a 19-carbon androgen, produced by both the adrenal gland (ACTH control) and gonads (LH or HCG control) and also by peripheral conversion from testosterone. Androstenedione has 20% of the androgenic potency of testosterone.

Androstenedione is most commonly measured in women for the investigation of polycystic ovarian syndrome (PCOS).

Androstenedione may be helpful in disorders of puberty. It is raised in cases of congenital adrenal hyperplasia (CAH) due to deficiency of the 21- or 11β-hydroxylase enzymes and may be useful in the diagnosis of these conditions and in the monitoring of glucocorticoid replacement therapy. Androgen secreting tumours of both the adrenal (adenoma and carcinoma) and ovary (arrhenoblastoma, hilar cell and granulosa cell) may result in high serum levels of androstenedione.

17-Hydroprogesterone (17OHP)

17-hydroxyprogesterone (17OHP) is a 21-carbon progestagen, produced by the adrenal gland (ACTH control) and gonads (LH or HCG control). 17OHP is a precursor to 11-deoxycortisol (11DOC) and is elevated in the most common form of congenital adrenal hyperplasia (CAH), 21-hydroxylase deficiency.

CAH is a group of inherited metabolic disorders of adrenal steroid hormone biosynthesis. The clinical features derive from a combination of under-production of either cortisol or aldosterone or both, and increased production of adrenal androgen precursors. The incidence of the classical disorder in Scotland is approximately 1/15,000.

Cortisol is the major glucocorticoid hormone synthesised from cholesterol in the adrenal cortex. Synthesis is stimulated by the anterior pituitary adrenocorticotrophic hormone (ACTH), which is under control of the hypothalamic peptide, corticotrophin-releasing hormone (CRH). 

As cortisol concentrations increase, the binding capacity of cortisol binding globulin in the circulation is exceeded, resulting in a disproportionate rise in urine cortisol concentrations. Urine cortisol measurement is useful as a screening test for cortisol excess (Cushing’s syndrome). Urine cortisol measurement can also be used as part of a dexamethasone suppression test. Multiple EMU cortisol measurements may also be useful in the investigation of possible cyclical Cushing’s.

Sample Requirements and Reference Ranges

• Sample Type: Urine (24 hr, random or early morning urine)
• Container: Plain urine container (no preservative)
• Precautions: None
• Minimum Volume: 10 mL
• Reference Range:
  • Adults (EMU): <40 nmol/mmol creatinine
  • Adults (24 hour): <165 nmol/24 hour
  • Children (≤10 yrs): <40 nmol/mmol creatinine

• Turnaround Time: 14 days
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: UK NEQAS

A urine steroid profile includes all major metabolites of steroids, including glucocorticoids, mineralocorticoids and precursors.

The test is used to identify genetic disorders of steroid metabolism, though the screening or diagnostic test for congenital adrenal hyperplasia should be serum 17-hydroxyprogesterone. Steroid profiling is also useful to detect abnormal steroid secretion from adrenal and gonadal tumours.

Sample Requirements and Reference Ranges

• Sample Type: Urine (Aliquot of 24 hour urine for adults or children aged 11 and over; random for children <11 years)
• Container: Plain urine container (no preservative)
• Precautions: None
• Minimum Volume: 10 mL preferred. Smaller volume acceptable for babies (min. 2 mL).

• Reference Range: Age and sex dependent. Interpretation accompanies each report.
• Turnaround Time: 28 days
• Method: Gas chromatography-mass spectrometry
• Quality Assurance: Sample exchange programme

Vitamin D is required for absorption of calcium and phosphate from the gut. The majority of vitamin D is produced in the skin when exposed to sunlight and the remainder obtained in the diet.

25-hydroxy vitamin D (25OHD) is the most abundant vitamin D metabolite in the circulation. It is relatively inactive but its measurement is the best indicator of vitamin D status.  25OHD exists in two forms, D3 and D2, and both are equally measured by the LC/TMS method.

Assessment of vitamin D status is important in patients with abnormal calcium or phosphate levels, possible osteomalacia and malabsorption, and osteoporotic patients before giving the first dose of IV bisphosphonates (to reduce the risk of drug induced hypocalcaemia).

NB. Request intervention procedures have been set up to reduce unnecessary testing. The request intervention interval for vitamin D is 340 days. All repeat requests within this period are reviewed by the Duty Biochemist and may be over-ridden if appropriate clinical details are provided.

Please refer to the NHSGGC Vitamin D Requesting and Prescribing Guidelines

Sample Requirements and Reference Ranges

• Sample Type: Serum
• Container: SST
• Precautions: None
• Minimum Volume: 500 μL (140 μL for neonates)
• Reference Range:
  • <25 nmol/L: Vitamin D deficient, consider supplementation
  • 25 – 50 nmol/L: Borderline low vitamin D, risk of secondary hyperparathyroidism, consider increase in vitamin D intake
  • >50 nmol/L: Adequate vitamin D

• Turnaround Time: 14 days
• Method: Liquid chromatography-tandem mass spectrometry
• Quality Assurance: UKNEQAS

1,25-dihydroxy vitamin D (1,25DHD) is the active form of vitamin D, produced primarily by the kidney by hydroxylation of 25-hydroxy vitamin D. 1,25DHD is the form of vitamin D that stimulates resorption of calcium from bone, intestinal absorption and renal reabsorption.

NB. 1,25DHD should not be used to determine vitamin D status; 25-hydroxy vitamin D is the best marker for this purpose.

Indications for 1,25DHD are limited. Measurement may be useful in the investigation of possible vitamin D-dependent rickets and in patients with hypercalcaemia to investigate possible excess 1,25DHD production e.g. granulomatous diseases (sarcoidosis, TB or lymphoma). 

Sample Requirements and Reference Ranges

• Sample Type: Serum
• Container: SST
• Precautions: None
• Minimum Volume: 250 μL
• Reference Range: 20 – 120 pmol/L (interim range pending further evaluation)
• Turnaround Time: 35 days
• Method: IDS iSYS
• Quality Assurance: DEQAS