Fa: Endocrine - Pathology - 2

Front 1

What are the characteristic signs / symptoms of hypothyroidism?

Back 1

- Cold intolerance (↓ heat production)
- Weight gain, ↓ appetite
- Hypoactivity, lethargy, fatigue, weakness
- Constipation
- ↓ Reflexes
- Myxedema (facial / periorbital)
- Dry, cool skin with coarse, brittle hair
- Bradycardia, dyspnea on exertion

Front 2

What are the characteristic signs / symptoms of hyperthyroidism?

Back 2

- Heat intolerance (↑ heat production)
- Weight loss, ↑ appetite
- Hyperactivity
- Diarrhea
- ↑ Reflexes
- Pretibial myxedema (Graves disease), periorbital edema
- Warm, moist skin with fine hair
- Chest pain, palpitations, arrhythmias, ↑ number and sensitivity of β-adrenergic receptors

Front 3

How do patients with hypothyroidism vs hyperthyroidism compare in terms of their bowel habits?

Back 3

- Hypothyroidism: constipation
- Hyperthyroidism: diarrhea

Front 4

How do patients with hypothyroidism vs hyperthyroidism compare in terms of their reflexes?

Back 4

- Hypothyroidism: decreased reflexes
- Hyperthyroidism: increased reflexes

Front 5

How do patients with hypothyroidism vs hyperthyroidism compare in terms of myxedema (swelling of the skin and underlying tissues giving a waxy consistency)?

Back 5

- Hypothyroidism: facial and periorbital myxedema
- Hyperthyroidism: pretibial myxedema (Graves disease), periorbital edema

Front 6

How do patients with hypothyroidism vs hyperthyroidism compare in terms of their skin and hair?

Back 6

- Hypothyroidism: dry, cool skin with coarse, brittle hair
- Hyperthyroidism: warm, moist skin with fine hair

Front 7

How do patients with hypothyroidism vs hyperthyroidism compare in terms of cardiac symptoms?

Back 7

- Hypothyroidism: bradycardia and dyspnea on exertion
- Hyperthyroidism: chest pain, palpitations, arrhythmias, ↑ number and sensitivity of β-adrenergic receptors

Front 8

Why do patients with hyperthyroidism sometimes have chest pain, palpitations, and arrhythmias?

Back 8

↑ number and sensitivity of β-adrenergic receptors

Front 9

What are the lab findings associated with hypothyroidism?

Back 9

- ↑ TSH (sensitive for 1° hypothyroidism)
- ↓ free T3 and T4
- Hypercholesterolemia (due to ↓ LDL receptor expression)

Front 10

What are the lab findings associated with hyperthyroidism?

Back 10

- ↓ TSH (if 1°)
- ↑ free or total T3 and T4
- Hypocholesterolemia (due to ↑ LDL receptor expression)

Front 11

How do thyroid disorders affect cholesterol? Mechanism?

Back 11

- Hypothyroidism: hypercholesterolemia due to ↓ LDL receptor expression
- Hyperthyroidism: hypocholesterolemia due to ↑ LDL receptor expression

Front 12

What is the most common cause of hypothyroidism in iodine-sufficient regions?

Back 12

Hashimoto Thyroiditis

Front 13

What causes Hashimoto Thyroiditis?

Back 13

Auto-immune disorder
- Anti-thyroid peroxidase and anti-thyroglobulin antibodies
- Associated with HLA-DR5

Front 14

What is there increased risk of in patients with Hashimoto Thyroiditis?

Back 14

Non-Hodgkin Lymphoma

Front 15

What may be an early, contradictory finding seen in patients with Hashimoto Thyroiditis?

Back 15

May be hyperthyroid early in course due to thyrotoxicosis during follicular rupture

Front 16

What are the histologic findings of Hashimoto Thyroiditis?

Back 16

Hürthle cells, lymphoid aggregate with germinal centers

Front 17

What does this histology indicate?

Back 17

Hürthle cells, lymphoid aggregate with germinal centers → Hashimoto Thyroiditis

Front 18

What are the expected thyroid findings on physical exam in a patient with Hashimoto Thyroiditis?

Back 18

Moderately enlarged, non-tender

Front 19

The presence of Hürthle cells should make you think of what?

Back 19

Hashimoto Thyroiditis

Front 20

What can cause severe fetal hypothyroidism (congenital hypothyroidism)?

Back 20

- Maternal hypothyroidism
- Thyroid agenesis
- Thyroid dysgenesis (most common cause in US)
- Iodine deficiency
- Dyshormonogenic goiter

Front 21

What are the findings of a patient with congenital hypothyroidism?

Back 21

6 P's:
- Pot-bellied
- Pale
- Puffy-faced child
- Protruding umbilicus
- Protuberant tongue
- Poor brain development

Front 22

What is cretinism?

Back 22

Congenital hypothyroidism

Front 23

What is the most common cause of congenital hypothyroidism in the US?

Back 23

Thyroid Dysgenesis

Front 24

What is wrong with the child on the left (before) and after treatment on the right?

Back 24

Congenital hypothyroidism

Front 25

What is the term for the self-limited hypothyroidism often following a flu-like illness?

Back 25

Subacute Thyroiditis (de Quervain)

Front 26

What happens in Subacute Thyroiditis (de Quervain)?

Back 26

- May be hyperthyroid early in course
- Self-limited hypothyroidism often following a flu-like illness

Front 27

What is the appearance of the thyroid histologically in Subacute Thyroiditis (de Quervain)?

Back 27

Granulomatous inflammation

Front 28

What cause of hypothyroidism is associated with a very tender / painful thyroid?

Back 28

Subacute Thyroiditis (de Quervain)
*de QuerVAIN is associated with PAIN*

Front 29

What are the findings in Subacute Thyroiditis (de Quervain)?

Back 29

- ↑ ESR
- Jaw pain
- Early inflammation
- Very tender thyroid
- Granulomatous inflammation of thyroid

Front 30

What causes granulomatous inflammation of the thyroid?

Back 30

Subacute Thyroiditis (de Quervain)

Front 31

What disease causes the thyroid to be replaced with fibrous tissue? What does this cause?

Back 31

Riedel Thyroiditis - causes hypothyroidism

Front 32

What happens in Riedel Thyroiditis?

Back 32

- Thyroid replaced by fibrous tissue (hypothyroid)
- Fibrosis may extend to local structures (eg, airway), mimicking anaplastic carcinoma

Front 33

What is Riedel Thyroiditis considered a manifestatoin of?

Back 33

Manifestation of IgG4-related systemic disease

Front 34

What are the findings of a patient's thyroid in Riedel Thyroiditis on physical exam?

Back 34

- Fixed
- Hard (rock-like)
- Painless goiter

Front 35

What are some other causes of hypothyroidism?

Back 35

- Iodine deficiency
- Goitrogens
- Wolff-Chaikoff effect
- Painless thyroiditis

Front 36

What are the causes of hyperthyroidism?

Back 36

- Toxic multinodular goiter
- Graves disease
- Thyroid storm

Front 37

What pathology is associated with focal patches of hyper-functioning follicular cells that work independently of TSH due to a mutation in the TSH receptor?

Back 37

Toxic Multinodular Goiter

Front 38

What is wrong in Toxic Multinodular Goiter?

Back 38

- Focal patches of hyper-functioning follicular cells
- Work independently of TSH due to mutation in TSH receptor
- ↑ Release of T3 and T4

Front 39

What does this histologic image of the thyroid show?

Back 39

Toxic Multinodular Goiter
- Follicles of various sizes distended with colloid (black arrows)
- Follicles are lined by flattened epithelium with areas of fibrosis and hemorrhage (blue arrows)
- Nodules are rarely malignant

Front 40

What is the term for thyrotoxicosis when a patient with iodine deficiency suddenly is made iodine replete?

Back 40

Jod-Basedow Phenomenon

Front 41

What happens in the Jod-Basedow Phenomenon?

Back 41

Thyrotoxicosis if a patient with iodine deficiency goiter is made iodine replete

Front 42

What is the most common cause of hyperthyroidism?

Back 42

Graves disease

Front 43

What is the underlying pathophysiology responsible for Graves disease?

Back 43

Auto-antibodies (IgG) stimulate TSH receptors on thyroid, retro-orbital fibroblasts, and dermal fibroblasts

Front 44

What kind of antibodies are associated with Graves disease? Hashimoto Thyroiditis?

Back 44

- Graves disease: IgG auto-Abs that stimulate TSH receptors
- Hashimoto Thyroiditis: anti-thyroid peroxidase and anti-thyroglobulin auto-Abs

Front 45

What are the implications of auto-antibodies (IgG) stimulating the TSH receptors on the thyroid?

Back 45

- Hyperthyroidism
- Diffuse goiter

Front 46

What are the implications of auto-antibodies (IgG) stimulating the TSH receptors on retro-orbital fibroblasts?

Back 46

Exophthalmos: proptosis, extraocular muscle swelling

Front 47

What are the implications of auto-antibodies (IgG) stimulating the TSH receptors on dermal fibroblasts?

Back 47

Pretibial myxedema

Front 48

When does Graves disease often present?

Back 48

During stress (eg, childbirth)

Front 49

What is the name for the stress-induced catecholamine surge seen as a serious complication of Graves disease and other hyperthyroid disorders?

Back 49

Thyroid Storm

Front 50

What causes a Thyroid Storm?

Back 50

Stress-induced catecholamine surge seen as a serious complication of Graves disease and other hyperthyroid disorders

Front 51

What are the symptoms of a Thyroid Storm?

Back 51

- Agitation
- Delirium
- Fever
- Diarrhea
- Coma
- Tachyarrhythmia (cause of death)

Front 52

What lab value is possibly elevated in Thyroid Storm? Why?

Back 52

↑ ALP due to ↑ bone turnover

Front 53

How do you treat Thyroid Storm?

Back 53

Treat with the 3 P's:
- β-blockers (eg, Propranolol)
- Propylthiouracil
- Corticosteroids (eg, Prednisolone)

Front 54

What are the indications for thyroidectomy?

Back 54

Treatment option for thyroid cancers and hyperthyroidism

Front 55

What are the potential complications of thyroid cancer?

Back 55

- Hoarseness: due to recurrent laryngeal nerve damage
- Hypocalcemia: due to removal of parathyroid glands
- Transection of inferior thyroid artery

Front 56

What are the types of thyroid cancers?

Back 56

- Papillary carcinoma
- Follicular carcinoma
- Medullary carcinoma
- Undifferentiated / anaplastic carcinoma
- Lymphoma

Front 57

If you see this on a sample of the thyroid, what diagnosis do you need to think of?

Back 57

Papillary Carcinoma of the thyroid
- Empty appearing nuclei ("Orphan Annie" eyes)

Front 58

What is the most common type of thyroid cancer? Associations?

Back 58

- Empty-appearing nuclei (Orphan Annie eyes), psamomma bodies, nuclear grooves
- Increased risk with RET and BRAF mutations and childhood irradiation
- Excellent prognosis

Front 59

What are the histologic findings of Papillary Carcinoma of the thyroid?

Back 59

- Empty-appearning nuclei ("Orphan Annie" eyes)
- Psammoma bodies
- Nuclear grooves

Front 60

What can increase your risk of getting Papillary Carcinoma of the Thyroid?

Back 60

- RET mutations
- BRAF mutations
- Childhood irradiation

Front 61

Which types of thyroid cancer are associated with a good prognosis?

Back 61

- Papillary Carcinoma (excellent prognosis, most common type)
- Follicular Carcinoma (good prognosis)

Front 62

Which type of thyroid cancer has a very poor prognosis?

Back 62

Undifferentiated / Anaplastic Carcinoma of thyroid

Front 63

What are the characteristics of a Follicular Carcinoma of the thyroid?

Back 63

- Good prognosis
- Invades thyroid capsule (unlike follicular adenoma)
- Uniform follicles

Front 64

What type of thyroid cancer arises from parafollicular "C cells"?

Back 64

Medullary Carcinoma of the thyroid

Front 65

What is the origin of Medullary Carcinoma of the thyroid? What does it produce?

Back 65

- From parafollicular "C cells"
- Produces calcitonin

Front 66

If you see this on a sample of the thyroid, what diagnosis do you need to think of?

Back 66

Medullary Carcinoma of the thyroid
- Solid sheets of cells with amyloid deposition (arrow)
- Amyloid stroma

Front 67

What is Medullary Carcinoma of the thyroid associated with?

Back 67

- MEN 2A and 2B
- RET mutations

Front 68

What type of thyroid cancer is more common in older patients?

Back 68

Undifferentiated / Anaplastic Carcinoma of thyroid

Front 69

What are the characteristics of Undifferentiated / Anaplastic Carcinoma of thyroid?

Back 69

- Affects older patients
- Invades local structures
- Very poor prognosis

Front 70

Which type of thyroid cancer is associated with Hashimoto thyroiditis?

Back 70

Lymphoma