Metabolic Disorders of the Thyroid and Adrenal Glands

Question 1

metabolic syndrome

Answer 1

a cluster of metabolic risk factors; excessive abdominal fat, high blood pressure, high triglyceride and/or cholesterol levels, high blood sugar. These risk factors can result in serious disease, such as heart disease and type 2 diabetes

Question 2

inborn errors of metabolism- rare disorders (hundreds are known, such as)

Answer 2

–Carbohydrate metabolism (ex: glycogen storage disease)
–Amino acid metabolism (ex: phenylketonuria)
–Organic acid metabolism (ex: alcaptonuria)
–Urea Cycle
–Fatty acid metabolism
–Porphyrin metabolism
–Purine Pyrimidine metabolism
–Steroid metabolism
–Mitochondrial function
–Peroxisomal function
–Lysosomal storage diseases
–Metal metabolism
–Congenital disorders of glycosylation
–Congenital disorders of creatine metabolism

Question 3

diseases of the thyroid gland (3)

Answer 3

–Goiter (abnormally large thyroid)
–Graves disease (hyperthyroidism)
–Hashimoto’s disease (hypothyroidism)

Question 4

diseases of the adrenal gland (2)

Answer 4

–Addison’s disease (aldosterone and cortisol insufficiency)

–Cushing’s syndrome (cortisol excess)

Question 5

what is the largest endocrine gland in the body? weight?

Answer 5

thyroid

15-20 gm

Question 6

what does the thyroid produce

Answer 6

thyroid hormones and calcitonin

Question 7

location of the thyroid

Answer 7

it sits between anterior to the trachea

Question 8

physical description of the thyroid

Answer 8

consists of two lobes and a central isthmus, which gives it a bow tie like shape

Question 9

the thyroid is the only tissue in the body capable of

Answer 9

absorbing iodine

Question 10

Iodine deficiency can lead to a variety of health and developmental consequences known as

Answer 10

iodine deficiency disorders (IDDs)

Question 11

what is the most widely used strategy to control and eliminate IDDs?

Answer 11

universal salt iodization

Question 12

universal salt iodization aims for consumption of adequately iodized salt in more than

Answer 12

90 per cent of households. However, this goal is a long way from being met

Question 13

Iodine deficiency is especially damaging during

Answer 13

the early stages of pregnancy and in early childhood

Question 14

In their most severe forms, IDDs can lead to (4)

Answer 14

cretinism, stillbirth and miscarriage; even mild deficiency can cause a significant loss of learning ability

Question 15

Adequately iodized salt can protect children from

Answer 15

brain damage, but only three quarters of the world’s households are using it. In 2013, more than 35 million newborns were unprotected from the lifelong consequences of brain damage associated with iodine deficiency

Question 16

one of the most common glandular disorders of the endocrine system

Answer 16

thyroid dysfunction

Question 17

how much of the world lives in areas of iodine deficiency?

Answer 17

1/3

Question 18

incidence of thyroid disorders

Answer 18

higher in females (9%) vs males (2%)

Question 19

abnormal thyroid prevalence

Answer 19

about 15% of the population

Question 20

most common findings of abnormal thyroid

Answer 20

thyroid nodules

Question 21

what is the major form of thyroid hormone found in the blood?

Answer 21

thyroxine, T4

Question 22

T4 is cleared into

Answer 22

3, 5, 3’ triiodothyronine (T3)

3, 3’, 5’ triiodothyronine (reverse T3)

Question 23

metabolically active form of T3

Answer 23

3, 5, 3’ triiodothyronine (T3)

Question 24

metabolically inactive form of T3

Answer 24

3, 3’, 5’ triiodothyronine (reverse T3)

Question 25

T4 is the major form found in blood, because

Answer 25

it has a longer half-life than T3

Question 26

T4 is converted to active T3 in target cells by the

Answer 26

deiodinase enzyme (or iodide peroxidase) Iodothyronine deiodinase.

Question 27

three isoforms (Type 1, 2 and 3) of Iodothyronine deiodinase and these enzymes contains a

Answer 27

selenium metal ion (in the form of selenocystiene)

Question 28

Selenium deficiency can lead to

Answer 28

decreased T3 levels

Question 29

Synthesis of thyroid hormones involves the protein

Answer 29

thyroglobulin

Question 30

TRH

Answer 30

thyrotropin releasing hormone

Question 31

TSH

Answer 31

thyroid stimulating hormone

Question 32

how is T4/T3 production regulated?

Answer 32

negative feedback regulation look at the levels of the pituitary and hypothalamus

Question 33

production of T4/T3

Answer 33

hypothalamus released TRH which stimulates the pituitary gland to release TSH which stimulates the thyroid gland to produce and secrete T3 and T4 which is converted to T3 in peripheral tissues

Question 34

Hyperthyroidism often

Answer 34

mimics other diseases

Question 35

hyperthyroidism can greatly accelerate your body’s

Answer 35

metabolism

Question 36

common symptoms of hyperthyroidism include (5)

Answer 36

–Heart problems: arrhythmia or atrial fibrillation –Osteoporosis: too much thyroxine interferes with process of bone formation and calcium handling –Eye problems: Graves ophthalmopathy –Red swollen skin: increased sensitivity to heat –Thyrotoxic crisis: sudden intensification of symptoms –Abnormal thermal regulation: night “sweats” –Brittle hair

Question 37

Graves Disease

Answer 37

Autoimmune disorder resulting in overproduction of thyroid hormones

Question 38

~30% of patients develop

Answer 38

Graves’ ophthalmopathy

Question 39

The autoimmune reaction is due to

Answer 39

an antibody that binds to the thyrotropin receptor, which stimulates the thyroid to overproduce thyroid hormones

Question 40

In rare circumstances patients can develop a

Answer 40

thyroid storm or thyrotoxic crisis. This is a life-threatening condition and must be treated immediately

Question 41

who is most likely to get hypothyroidism?

Answer 41

More common in women over age 60, but anyone, including infants can develop hypothyroidism

Question 42

common symptoms of hypothyroidism (8)

Answer 42

``` –Fatigue–Sensitivity to cold –Constipation –Dry skin –Weight gain –Puffy face –Hoarseness –Muscle weakness, aches, tenderness and stiffness –Thinning hair ```

Question 43

Hashimoto Syndrome

Answer 43

Autoimmune disease (T-cell mediated) in which your immune system attacks the thyroid

Question 44

Hashimoto Syndrome results in

Answer 44

hypothyroidism

Question 45

Hashimoto Syndrome affects about

Answer 45

5 in 100 people in the US

Question 46

who is most likely to develop Hashimoto Syndrome

Answer 46

Women are ~8X more likely to develop than men

Question 47

Several diseases are risk factors, such as (6)

Answer 47

Addison’s disease, celiac disease, pernicious anemia, Sjogren’s syndrome, type 1 diabetes, vitiligo

Question 48

patients with Hashimoto Syndrome often develop a --- as the disease progresses

Answer 48

goiter

Question 49

dental complications of radioiodine therapy (2)

Answer 49

* Xerostomia or dry mouth | * Increased risk of caries due to changes in oral microbiome

Question 50

radioiodine therapy is a treatment of

Answer 50

thyroid cancer because the thyroid is the only organ that produces iodine

Question 51

The danger of low dietary iodine is further compounded by your body’s decreased ability to utilize it, the result of contamination by a ubiquitous environmental toxin called

Answer 51

perchlorate

Question 52

what is perchlorate used for?

Answer 52

Originally developed for explosives and rocket fuel, perchlorate now pervades ground water and food supplies throughout the US. It’s even used as a flavor-enhancer in certain foods.

Question 53

how does perchlorate act?

Answer 53

blocks the thyroid gland’s ability to absorb and utilize dietary iodine, an effect that is of concern when iodine intake drops off.

Question 54

5 steps to do an iodine deficiency test on yourself

Answer 54

1. Use tincture of iodine (the orange variety) to paint a 2-3-inch square patch on the inside of your forearm, the inside of a thigh, or your abdomen. 2. Inspect the painted area in less than 8 hours. If all the color is gone, then you definitely have an iodine deficiency. 3. If after 24 h, all the color is gone, you also likely need iodine. 4. If the color simply remains on your arm and begins to slowly fade in color after 24 h, you have reached iodine sufficiency. 5. You can repeat the test in a month or so after supplementing with iodine to see how you’re doing.

Question 55

where are adrenal glands located?

Answer 55

on top of the kidneys

Question 56

two parts of the adrenal glands?

Answer 56

cortex and medulla

Question 57

what does the cortex produce? (3)

Answer 57

mineralocorticoids glucocorticoids adrenal androgens

Question 58

what does the medulla produce?

Answer 58

catecholamines

Question 59

main mineralocorticoid

Answer 59

aldosterone

Question 60

main glucocorticoid

Answer 60

cortisol

Question 61

main adrenal androgens (2)

Answer 61

DHEA | testosterone

Question 62

main catecholamines (2)

Answer 62

adrenaline (epinephrine) | noradrenaline (norepinephrine)

Question 63

examples of diseases of adrenal gland dysfunction in humans (4)

Answer 63

Cushing disease addisons disease hyperaldosteronism pheochromocytoma

Question 64

Cushing disease

Answer 64

adrenal overproduction of cortisol

Question 65

Addisons diease

Answer 65

adrenal underproduction of cortisol

Question 66

hyperaldosteronism

Answer 66

increase aldosterone, which control blood pressure and body stat and potassium levels

Question 67

phenochromocytoma

Answer 67

high levels of adrenaline

Question 68

cushings syndrome oral signs (3)

Answer 68

fatty tissue deposition (moon face) osteoporosis (pathological fractures of the mandible, maxilla, or alveolar bone delayed healing of fractures and also soft tissue injuries

Question 69

Addisons disease (oral signs) (2)

Answer 69

bronzing hyperpigmentation of the skin | oral mucosal melanosis (buccal muscosa, tongue)

Question 70

Addisons disease causes an increased production of melanin, results in

Answer 70

melanotic macules in the oral mucosa

Question 71

the thyroid gland produces (2)

Answer 71

T3 and T4

Question 72

what are T3 and T4 produced from?

Answer 72

iodination of thyroglobulin

Question 73

thyroglobulin is degraded to release (2)

Answer 73

T3 and T4

Question 74

major circulating form

Answer 74

T4