Читать книгу Essential Endocrinology and Diabetes - Richard I. G. Holt - Страница 94

Most endocrinology testing is ‘static’; hormones and metabolites are measured as they circulate at any one time. However, rhythmical, pulsatile or variable hormone secretion makes interpretation of single random samples meaningless or misleading (Chapter 1). For some hormones, such as GH, a clinical impression can be gained from a series of six to eight measurements during the course of a day. Alternatively, dynamic testing may be necessary where, based on understanding normal physiology, responses are measured following a stimulus. This might be metabolic, such as insulin‐induced hypoglycaemia to study the expected rise in serum GH and cortisol (Chapter 5), or the administration of glucose during a glucose tolerance test to diagnose diabetes (Chapter 11). Alternatively, the stimulus might be hormonal, such as injecting adrenocorticotrophic hormone (ACTH; the anterior pituitary hormone) to measure secretion of cortisol (the adrenocortical hormone). In this sense, fasting measurements, as required for serum lipids or commonly for glucose, could be viewed as dynamic, where fasting is the stimulus.

Table 4.1 Endocrine reference ranges

Adult reference hormone	Range	Units	Range	Unit
17‐Hydroxyprogesterone (male)	0.18–9.1	nmol/L	5.9–300	ng/dL
17‐Hydroxyprogesterone (female)	0.6–3.0	nmol/L	20–99	ng/dL
Adrenocorticotrophic hormone (ACTH, 9 AM)	0–8.8	pmol/L	0–40	ng/L
Aldosterone (AM; out of bed for 2 h; seated 5–15 min)a	100–500	pmol/L	3.6–18.1	ng/dL
Androstenedione (adult male and female)	2.1–9.4	nmol/L	60–270	ng/dL
Anti‐Müllerian hormone (to indicate poor ovarian reserve)b	>7	pmol/L	>1	ng/mL
Chromogranin A (fasting)	0–5.2	nmol/L	0–250	ng/ml
Cortisol (9 AM)c	140–700	nmol/L	5–25	μg/dL
Cortisol (midnight)	80–350	nmol/L	2.9–12.5	μg/dL
Cortisol (post low dose dexamethsaone)	<50	nmol/L	1.8	μg/dL
Cortisol (urinary free)	0–280	nmol/24 h	0–10	μg/24 h
Epinephrine (adrenaline)	0–546	pmol/L	0–100	pg/mL
Epinephrine (adrenaline; urine)	0–1.0	μmol/24 h	0.5–20	μg/24 h
Follicle‐stimulating hormone (FSH)
Males (adult)	1.0–8.0	U/L	–	–
Females
Early follicular phase	1.0–11.0	U/L	–	–
Post‐menopausal	>30	U/L	–	–
Gastrin (fasting)	0–40	pmol/L	0–154	pg/mL
Glucagon (fasting)	0–50	pmol/L	0–139	pg/mL
Glucose
Fasting (normal)	<6.1	mmol/L	<110	mg/dL
Fasting (impaired fasting glycaemia; ‘pre‐diabetes’)	6.1–6.9	mmol/L	110–125	mg/dL
Fasting (diabetes)	≥7.0	mmol/L	≥126	mg/dL
Post‐glucose tolerance test (normal)	<7.8	mmol/L	<140	mg/dL
Post‐glucose tolerance test (impaired glucose tolerance; ‘pre‐diabetes’)	7.8–11.0	mmol/L	140–200	mg/dL
Post‐glucose tolerance test (diabetes)	≥11.1	mmol/L	≥200	mg/dL
Growth hormone
After a glucose load	<0.3d	ng/mL	<0.8	mU/L
Stress‐induced [e.g. glucose <2.2 mmol/L (<40 mg/dL)]	>6.7	ng/mL	>17	mU/L
HbA1c (to diagnose diabetes)e	≥47	mmol/mol	≥6.5	%
Insulin
Fasting	<69.5	pmol/L	<10	mU/L
When glucose <2.5 mmol/L (<45 mg/dL)	<34.7	pmol/L	<5	mU/L
When glucose <1.5 mmol/L (<27 mg/dL)	<13.9	pmol/L	<2	mU/L
Insulin‐like growth factor If
25–39 years	114–492	ng/mL	–	–
40–54 years	90–360	ng/mL	–	–
>54 years	71–290	ng/mL	–	–
Luteinizing hormone (LH)
Males	0.5–9.0	U/L	–	–
Females
Early follicular phase	0.5–14.5	U/L	–	–
Postmenopausal	>20	U/L	–	–
Metanephrine	0–0.5	nmol/L	0–99	pg/mL
Metanephrine (urine)	0–2.0	μmol/24 h	24–96	μg/24 h
Norepinephrine (noradrenaline)	0–3.5	nmol/L	0–600	pg/mL
Norepinephrine (urine)	0–0.2	μmol/24 h	15–80	μg/24 h
Normetanephrine	0–1.0	nmol/L	0–180	pg/mL
Normetanephrine (urine)	0–3.0	μmol/24 h	75–375	μg/24 h
Oestradiol
Males	37–130	pmol/L	10–35	pg/mL
Females
Early follicular phase	70–600	pmol/L	19–160	pg/mL
Mid‐cycle	700–1900	pmol/L	188–371	pg/mL
Luteal phase	300–1250	pmol/L	81–337	pg/mL
Pancreatic polypetide (fasting)	0–100	pmol/L	0–418.5	pg/mL
Parathyroid hormone (PTH)	0–4.4	pmol/L	0–41.5	pg/mL
Prolactin	80–500	mU/L	3.8–23.6	ng/mL
Progesterone (day 21, luteal phase)	>30	nmol/L	>9.4	ng/mL
Renin (AM; out of bed for 2 h; seated 5–15 min)a , g	2–30	mU/L	0.9–13.6	pg/mL
Sex hormone‐binding globulin
Females	40–120	nmol/L	–	–
Males	20–60	nmol/L	–	–
Somatostatin (fasting)	0–150	pmol/L	0–245	pg/mL
Testosterone
Males	8–35	nmol/L	230–1000	ng/mL
Females	0.7–3.0	nmol/L	20–85	ng/mL
Thyroglobulin	1.5–30	pmol/L	1–20	μg/L
Thyroid‐stimulating hormone (TSH)	0.3–5.0	mU/L	–	–
Thyroxine, free (fT4)	9–23	pmol/L	0.7–1.8	ng/dL
Tri‐iodothyronine, free (fT3)	3.1–7.7	pmol/L	0.2–0.5	ng/dL
Vasoactive intestinal polypeptide (fasting)	0–30	pmol/L	102	pg/mL
Vitamin D (25‐OH‐cholecalciferol)	4–40	nmol/L	1.6–16	ng/mL
Vitamin D (1,25‐OH‐cholecalciferol)	48–110	pmol/L	20–45.8	pg/mL

Ranges shown are for serum unless otherwise stated. Ranges vary slightly between laboratories due to differences in the methods employed. These examples are only intended to be illustrative and readers should check with their local laboratories.

^a Most informative as part of the aldosterone:renin ratio (Chapter 6).

^b Age dependent. Low values indicate poor ovarian reserve.

^c Salivary assays are variable and require establishment of local normal ranges.

^d Greater suppression from glucose load can be demonstrated using newer more sensitive immunoradiometric or chemiluminescent assays.

^e The World Health Organization and the American Diabetes Association have endorsed HbA_1c for the diagnosis of diabetes above or equal to these values.

^f IGF‐I values are approximate as age‐ and sex‐adjusted ranges are required.

^g Renin is also measured as ‘plasma renin activity’ when 1 mU/L equates to 1.56 pmol/L/min (0.12 ng/mL/h).