MLAB 2401: Clinical Chemistry Keri Brophy-Martinez Disorders of the Adrenal Gland.

MLAB 2401: Clinical ChemistryKeri Brophy-Martinez

Disorders of the Adrenal Gland

Addison’s Disease

• What is it?– Atrophy or destruction of adrenal cortex

(PRIMARY)• Idiopathic• Autoimmune adrenalitis• Tuberculosis

– Adrenal insufficiency (SECONDARY)• Hypothalamic/pituitary disease

Clinical Features: Addison’s Disease

Laboratory • Decreased cortisol levels

– Both serum & urine

• Decreased aldosterone• Increased ACTH

– > 200 pg/mL

Manifestations• Increased skin pigmentation• Tiredness• Intestinal issues• Hypotension• Hypoglycemia• Hyperkalemia• Hyponatremia/hypocholoremia• Loss of body hair• Depression

Addison’s Disease

Low Aldosterone

Increased pigment of skin

Increased MSH

Shrunken Adrenal Cortex

Increased ACTH

Low cortisol

No inhibition of ACTH

Cushing’s Syndrome

• Caused by:– Excess glucocorticoid production

• Cortisol-secreting adrenal carcinoma or adenoma

– Prolonged exogenous steroid use• iatrogenic

Laboratory Features

• Increased serum cortisol– Lack of diurnal variation

of cortisol

• Hyperglycemia

Sunheimer, R., & Graves, L. (2010). Clinical Laboratory Chemistry. Upper Saddle River: Pearson

Cushing’s Syndrome

• Manifestations– Weight gain in face and

abdomen– Buffalo hump back– Muscle

wasting/weakness– Easy bruising– Hypertension– Osteoporosis– Hyperglycemia

Conn’s Syndrome

• Caused by:– Aldosterone-secreting adrenal adenoma of

adrenal cortex (Primary)– Disorders within the renin-angiotensin system

(Secondary)

Clinical Features: Conn’s Syndrome

Laboratory• Low serum potassium• High serum sodium• High aldosterone levels• Acid/base imbalances

Manifestations• Muscle weakness• Increased urination• Hypertension

Adrenal Medulla Disorders

• Pheochromocytoma– Benign or malignant tumors in the adrenal

medulla– Causes hypertension

• Neuroblastoma/Ganlioneuromas– Common malignant tumors in pediatric patients

Disorders of Sexual Development

Testosterone

• Hyperandrogenemia– Increased testosterone production

• In females: hirsutism ( see next slide)

– Due to tumors in hypothalamus, testicles, or congenital adrenal hyperplasia

• Hypoandrogenemia– Decreased testosterone production– Due to infections, tumors, congenital disorders, or

decreased function of pituitary/ hypothalamus

Hirsutism

• Abnormal, abundant, hair growth( lip, chin, side burn, neck)

• Loss of female sex characteristics

• Ethnic origin important– Italians, eastern

europeans, eastern Indian, Irish

hCG & Human placental lactogen

• hCG– Increased

• Hydatidiform mole, choriocarcinoma, pre-eclamptic toxemia

– Decreased• Threatened abortion, ectopic pregnancy

• Human placental lactogen– Normal to rise throughout gestation– Decreased levels suggest placental malfunction or fetal

distress

Estrogen

• Hyperestrinism– Overproduction of estrogen– Females

• Early puberty• Infertility & irregular menses• Postmenopausal bleeding

– Males• Testicular atrophy• Breast enlargement

Estrogen

• Hypoestrinism– Decreased production of estrogen

• Ovarian insufficiency• Delayed puberty• Amenorrhea• Turner Syndrome

Progesterone

• Hyperprogesteronemia– Prevents menstrual cycle

• Hypoprogesteronemia– Results in infertility– Abortion of fetus

Menstrual Cycle Abnormalities• Average cycle is 28 days• Menopause between 45-55 years

• Amenorrhea– Absence of menses– Primary: never menstruated– Secondary: Had at least one menstrual cycle

• Oligomenorrhea– Irregular menses– Cycle length in excess of 35- 40 days

• Menorrhagia– Uterine bleeding > 7 days

References

• Bishop, M., Fody, E., & Schoeff, l. (2010). Clinical Chemistry: Techniques, principles, Correlations. Baltimore: Wolters Kluwer Lippincott Williams & Wilkins.

• Sunheimer, R., & Graves, L. (2010). Clinical Laboratory Chemistry. Upper Saddle River: Pearson .

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