Thyroid Flashcards
0
Q
Reference range for TSH
A
0.5 to 4.5 mIU/L
1
Q
Drugs that inhibit TRH
A
Somatostatin and its analogs
2
Q
Drugs that can inhibit TSH
A
Dopamine
Dopamine agonists
High levels of glucocorticoid
3
Q
T4 other name
A
Thyroxine
4
Q
Free t4 reference range
A
0.7 to 1.9 ng/dL
5
Q
Half life of thyroxine
A
7-10 days
6
Q
T3 other name
A
Triiodothyronine
7
Q
Half life of triiodothyronine
A
24 hours
8
Q
Hyperthyroidism diagnosis with tsh and t4
A
Tsh low
T4 elevated
9
Q
Primary causes of hyperthyroidism
A
Graves' disease Toxic multinodular goiter Toxic adenoma Thyroid cancer Iodine excess
10
Q
Most common cause of hyperthyroidism
A
Graves’ disease
11
Q
Secondary causes of hyperthyroidism
A
Tsh secreting pituitary tumors
Gestational thyrotoxicosis
12
Q
Which sex is at greater risk for Graves’ disease
A
Female
13
Q
Tshr-sab antibodies seen in what disease
A
Graves’ disease
14
Q
Pathology of Graves’ disease
A
Antibodies increase tsh release causing increase t4 release
15
Q
Visual findings with Graves’ disease
A
Opthalmopathy
Eye lid retraction
16
Q
Skin signs and symptoms in Graves’ disease
A
Non pitting edema
17
Q
Treatment options for Graves’ disease
A
Radioactive iodine
Ptu
Mmi
Surgery
18
Q
Thyroid radiology scan also called
A
Radio iodine uptake RAIU
19
Q
Thyroid radiology testing contraindicated in who
A
Pregnant or breastfeeding
20
Q
Symptoms of hyperthyroidism
A
Nervousness Fatigue Weakness Increased perspiration Heat intolerance Tremor Hyperactivity, irritability Palpitations Increased appetite Weight loss Menstrual disturbance Diarrhea
21
Q
Signs of hyperthyroidism
A
Hyperactivity Tachycardia Atrial fibrillation Hyperreflexia Warm skin Moist skin Goiter Muscle weakness Ophthalmopathy (graves disease) Dermopathy (Graves' disease )
22
Q
Non pharm therapy for hyperthyroidism
A
Avoid strenuous exercise Avoid caffeine Avoid Otc decongestant Avoid iodine supplement and contrast media Smoking cessation
23
Q
Who is indicated for thyroid surgery
A
Large goiters
Thyroid cancer
Unresponsive to therapy
24
Pharm treatment options for hyperthyroidism
Iodine
Radioactive iodine
Anti thyroid drugs
Beta blockers
25
Anti thyroid drugs used
Propylthiouracil
| Methimazole
26
Beta blockers used for hyperthyroidism
```
Metoprolol
Atenolol
Propranolol
Nadolol
Esmolol
```
27
How do beta blockers help in hyperthyroidism
Alleviate symptoms such as palpitations
28
When is esmolol used
Thyroid storm
29
Why are non selective beta blockers and nadolol used for hyperthyroidism
Reduces the conversion of t4 to t3
30
Anti thyroid drugs also called
Thionamides
31
Anti thyroid drugs not recommended in who
Low RAIU hyperthyroidism
32
Which anti thyroid drug is usually preferred
Methimazole
33
When is methimazole not preferred
Thyroid storm
First trimester
Methimazole allergy
34
Methimazole duration of treatment
Ideally 12-18 months
| If euthyroid discontinue
35
Initial dose of methimazole
10-20 mg daily
36
Propylthiouracil duration of treatment
Short time frame
37
Propylthiouracil initial dose
50-150 mg TID
38
Side effects of anti thyroid drugs
```
Hepatotoxic
Agranulocytosis
Arthralgia
Skin rash
GI upset
```
39
Boxed warning on propylthiouracil
Hepatotoxic
40
Define thyrotoxicosis
Any syndrome with increased thyroid hormones
41
Risk with hyperthyroidism in pregnancy
Increased risk of miscarriage
42
Pregnancy effect of hyperthyroidism
Worsens
43
Why use propylthiouracil in first trimester
Methimazole teratogenic in first trimester
44
Which anti thyroid drug to use while breastfeeding
Methimazole
45
Which hyperthyroidism treatment preferred in pediatric
Methimazole
| Consider beta blockers
46
Avoid which two hyperthyroidism treatments during pregnancy
Radioactive iodine
| Surgery if possible
47
What is thyroid storm
Severe form of thyrotoxicosis
48
Thyroid storm labs
Tsh undetectable
| T4 and t3 elevated
49
Signs and symptoms of thyroid storm
```
High fever
Tachycardia
Tachypnea
Dehydration delirium
Coma
GI disturbances
```
50
Causes of thyroid storm in a hyperthyroidism patient
Trauma
Surgery
Radioactive iodine treatment
Sudden withdrawal from anti thyroid meds
51
Treatment options for thyroid storm
```
Supportive care
Steroids
Short acting beta blockers
Oral lodine
Anti thyroid drugs
```
52
Iodide MOA
Inhibit thyroid hormone synthesis and release
53
Iodide recommended when
Prior to thyroid surgery (graves)
Thyroid storm
Non thyroid patients post nuclear attack
54
Name two iodide solutions
Potassium iodide
| Lugols solution
55
Recommended dose of iodide
120-400 mg per day
56
Side effects of iodide treatment
Palpitations
Depression
Gynecomastia
Pustular skin pockets
57
MOA of radioactive iodine
Thyroid cell necrosis over a few weeks
58
When is radioactive iodine recommended
Graves' disease
Toxic adenomas
Toxic multinodular goiters
59
When is radioactive iodine contraindicated
Pregnancy
60
Do you give radioactive iodine with high t4 levels
Pretreat with methimazole. Discontinue methimazole within 7 days of radioactive iodine
61
Side effects of radioactive iodine
Hypothyroidism
Sialadentis
Can worsen graves orbitopathy
62
What is sialadenitis
Salivary gland inflammation
63
What is subclinical hyperthyroidism
Low tsh
Normal t4
Maybe symptoms
64
How often to monitor tsh for subclinical hyperthyroidism without treatment
Every 6 months
65
Treat which patients with subclinical hyperthyroidism
Tsh less than 0.1 mIU/L
Post menopausal women
Cardiovascular disease
66
Why treat subclinical hyperthyroidism
Increase risk of bone density loss
| Increase risk of cardiovascular events
67
Screen who for hyperthyroidism
High risk
| Women over 50
68
Which individuals are at high risk for hyperthyroidism
Presence of nodular goiters
Concurrent endocrine disorders
Concurrent medications
Concurrent medical conditions
69
Which medications cause high risk of hyperthyroidism
```
Amiodarone
Alpha interferon
Lithium
Interleukin 2
Iodide contrast
```
70
Which medical conditions cause high risk of hyperthyroidism
Osteoporosis
Atrial fibrillation
Supra ventricular tachycardia
71
Hypothyroidism lab findings
High tsh
| Low t4
72
Causes of hypothyroidism
```
Primary gland failure
Insufficient gland stimulation by hypothalamus
Autoimmune thyroid disease
Iatrogenic causes
Drug causes
Disorder causes
```
73
What causes primary gland failure
Hashimoto disease
Iodine deficiency
Congenital abnormalities
74
What are iatrogenic causes of hypothyroidism
Post thyroid surgery
| Radioactive iodine treatment
75
Which drugs cause hypothyroidism
```
Lithium
Amiodarone
Interferon alpha
Interleukin 2
Ethionamide
Sulfonylurea
Valproic acid
Tyrosine kinase inhibitors
```
76
Name a disorder that can cause hypothyroidism
Postpartum thyroiditis
77
Who gets screened for hypothyroidism
Only high risk patients
78
Who is high risk for hypothyroidism
```
History or first degree relative with autoimmune
Radioactive iodine therapy
Head and neck radiation
Presence of a goiter
Family history of a goiter
Drugs that affect thyroid
Psych disorders
```
79
Who is at higher risk of hypothyroidism wig interferon alpha
Asians
| Thyroid antibodies
80
How does lithium cause hypothyroidism
Inhibits thyroid hormone secretion and synthesis
81
How does amiodarone cause hypothyroidism
Blocks conversion of t4 to t3
| Decreases t3 receptor binding
82
Effects of amiodarone on thyroid labs
Decrease t3
Increase t4
Increase tsh
83
Symptoms of hypothyroidism
```
Fatigue
Lethargy
Mental impairment
Depression
Cold intolerance
Dry skin
Weight gain
Decreased perspiration
Menstrual disturbances
Hair thinning or loss
Muscle weakness
Constipation
```
84
Signs of hypothyroidism
```
Slow speech
Hoarseness
Bradycardia
Delayed reflexes
Nonpitting edema
Diastolic hypertension
Elevated c reactive protein
Increased creatinine kinase
Increased triglycerides
Increased ldl
Hypothermia
```
85
Treatment options for hypothyroidism
Levothyroxine
Liothyronine
Dessicated thyroid
Liotrix
86
Levothyroxine brand name
Synthroid
| Levoxyl
87
Levothyroxine contains which thyroid hormones
T4
88
Gold standard for hypothyroidism
Levothyroxine
89
Levothyroxine typical dose
1-1.6 mcg/kg/day
90
Liothyronine brand name
Cytomel
91
Liothyronine thyroid hormones
T3
92
Dessicated thyroid brand name
Armour thyroid
93
Desiccated thyroid contains what thyroid hormones
T4 and t3
94
Liotrix brand name
Thyrolar
95
Liotrix thyroid hormones
T4 and t3 in a 4:1 ratio
96
When to check thyroid labs if brand and generic are switched
6 weeks
97
Dose of levothyroxine in patients less than 65 with no cardiovascular disease
1.6 mcg/kg/day
98
Levothyroxine dose in persons over 75
1mcg/kg/day
| Typical starting dose 25-50mcg
99
When to check tsh after starting levothyroxine
4-8 weeks
100
Separate levothyroxine how with calcium, iron, or prenatals
2 hours before or 6 hours after
101
Monitoring for levothyroxine
Tsh every 6-12 months with evaluations of symptoms
102
Hypothyroidism to euthyroid warfarin effects
Decrease dose as become euthyroid
103
Starting dose of levothyroxine in elderly with ischemic heart disease
12.5-50 mcg
104
After what age do pediatrics get adult doses of levothyroxine
12 years
105
Pregnancys effect on thyroid hormone
Increase demand
106
Give what to patients on levothyroxine with normal labs but symptoms
T3/t4 combination
107
Possible cause of symptoms of hypothyroidism on treatment with normal labs
Type 2 deiodinase polymorphism
108
Triggers of myxedema coma in long standing hypothyroidism
Trauma
Infection
Stroke
Hypnotics or opiates
109
Signs or symptoms of myxedema coma
Cns depression
Respiratory depression
Cardiac complications
110
Treatment options for myxedema coma
Levothyroxine bolus Iv
Glucocorticoid
Combination t4/t3
111
Lab findings of subclinical hypothyroid
Elevated tsh (4.5-10)
Normal t4
Maybe symptoms
112
Treat who with subclinical hypothyroidism
```
Tsh greater than 10
Elevated antibody levels
Signs and symptoms
Pregnant
Tsh 5-10
```
113
Dangers of subclinical hypothyroidism
Increased cardiac mortality
Increased ldl
Neuropsychiatric signs
Decreased exercise tolerance
114
Hypothyroidism is linked to what other diseases
```
High cholesterol
Increased vascular resistance
Decreased cardiac output
Increased diastolic blood pressure
Dementia like state
Increased risk of miscarriage
```
