HYPERTHYROIDISM Flashcards
Essentials of diagnosis of a patient with Hyperthyroidism.
(1) Sweating, weight loss, heat intolerance, menstrual irregularity, tachycardia, tremor, stare (exophthalmos due to extraocular muscle edema)
(2) In Graves’ disease
(a) Goiter (often with bruit)
(b) Ophthalmopathy
(c) Thyroid stimulating immunoglobulins (activate TSH receptor in thyroid gland)
(3) In primary hyperthyroidism (thyroid is acting autonomously - i.e. the thyroid gland is producing hormones independent of the normal feedback loop with the pituitary gland).
(a) Increased free thyroxine (T4) and triiodothyronine (T3)
(b) Low thyroid-stimulating hormone (TSH)
General Considerations of a patient with Hyperthyroidism.
(1) Causes
(a) Graves’ disease (most common)
(b) Hashimoto’s thyroiditis may cause transient hyperthyroidism during initial phase and may occur postpartum (will eventually be hypothyroid)
(c) High serum human chorionic gonadotropin levels in first 4 months of
pregnancy, molar pregnancy, choriocarcinoma, and testicular
malignancies may cause thyrotoxicosis
Clinical Findings of a patient with Hyperthyroidism.
Signs:
(a) Fever
(b) Tachycardia
(c) Diaphoresis/sweating
(d) Tremors
(e) Disorientation/psychosis
(f) Goiter
(g) Exophthalmos
(h) Hyperreflexia
(i) Pretibial myxedema
Clinical Findings of a patient with Hyperthyroidism.
Symptoms:
(a) Weight loss despite increased appetite
(b) Dysphagia or dyspnea 2° to goiter
(c) Rash/pruritus/hyperhidrosis
(d) Palpation/chest pain
(e) Diarrhea
(f) Myalgias and weakness
(g) Nervousness/anxiety
(h) Menstral irregularities
(i) Heat intolerance
(j) Insomnia and fatigue
Clinical Findings of a patient with Hyperthyroidism. Thyroid Eye Skin Heart
(3) Thyroid
(a) Goiter (often with a bruit) in Graves’ disease
(b) Moderately enlarged, tender thyroid in subacute thyroiditis
(4) Eye
(a) Stare and lid lag
1) Physical exam where the examiner has the patient stare at the tip of the
examiner’s finger from approximately 1 foot away and is moved from upper
visual field quickly to the lower field. Seeing the entire pupil plus part of the
sclera just above is a positive sign - normally the upper lid will obstruct at
least part of the upper pupil even when looking down.
(b) Ophthalmopathy (chemosis, conjunctivitis, and mild proptosis) in 20-
40% of patients with Graves’ disease
(c) Diplopia may be due to coexistent myasthenia gravis
(5) Skin
(a) Moist warm skin
(b) Fine hair
(c) Onycholysis
(d) Dermopathy (myxedema) in 3% of patients with Graves’ disease
(6) Heart
(a) Palpitations or angina pectoris
(b) Arrhythmias
1) Sinus tachycardia
2) Premature atrial contractions
3) Atrial fibrillation or atrial tachycardia
(c) Thyrotoxic cardiomyopathy due to thyrotoxicosis
(d) (Rarely) heart failure
Clinical Findings of a patient with Hyperthyroidism.
Thyroid storm
(a) This disorder, rarely seen today, is an extreme form of thyrotoxicosis that
may be triggered by stressful illness, thyroid surgery, or Radioactive iodine (RAI) administration.
(b) Manifested by marked delirium, severe tachycardia, vomiting, diarrhea,
dehydration and, in many cases, very high fever.
(c) The mortality rate is high.
Lab/imaging findings of a patient with Hyperthyroidism.
(1) TSH will be low (normal negative feedback response to excess T4/ T3).
(2) T4 sometimes normal but T3 elevated
Treatment of a patient with Hyperthyroidism.
Graves’ disease
(a) Radioactive Iodine –
1) Administration of 131 I is an excellent method of destroying overactive
thyroid tissue.
2) Treatment of choice for active duty service members since thyroid
suppressing medications (methimazole and propylthiouracil) generally
preclude ongoing military service (not deployable).
(b) Propranolol (β blocker)
1) Generally used for symptomatic relief of tachycardia, tremors,
diaphoresis, and anxiety until the hyperthyroidism is resolved.
2) Treatment is usually begun with Propranolol ER 60 mg PO BID
3) Increased every 2-3 days to a maximum daily dose of 320 mg or higher
with guidance from MO. Dosing is for symptom control and does not
address underlying hyperthyroid state.
Treatment of a patient with Hyperthyroidism.
Long term treatment:
(a) Radioactive iodine is the most widely recommended permanent
treatment of hyperthyroidism.
(b) Another permanent cure for hyperthyroidism is to surgically remove all or part of the thyroid gland.
1) Both long term treatment options results in the patient developing hypothyroidism and lifelong need for thyroid hormone replacement (levothyroxine) is expected.
Disposition of a patient with Hyperthyroidism.
MEDEVAC
Complications of a patient with Hyperthyroidism.
(1) As indicated under clinical findings
