Hyperthyroidism

Symptoms:

• General – fine tremor, anxiety, irritability, emotional lability, panic attacks, heat intolerance, sweating
• CV – palpitations
• GI – increased appetite, diarrhea, wt loss
• GU – menstrual dysfunction, infertility
• Graves’ – blurring of vision, photophobia, double vision, increased lacrimation

Signs

• General – hyperreflexia
• CV – tachycardia, atrial fibrillation
• Neuro – proximal muscle weakness
• Skin – fine hair, moist warm skin, vitiligo, soft nails
• MSK –  bone mass, hypercalcemia, muscle wasting
• Graves’ – exophthalmos, lid retraction, lid lag, clubbing, acropachy, pretibial myxedema

 

Physical Exam

Etiology:        

• Graves’ disease (80 – 90 %)
• Hashimoto’s thyroiditis
• Subacute thyroiditis
• Toxic multinodular goiter
• Toxic adenoma
• Iatrogenic and factitious

Differential Diagnosis:

• Anxiety disorder
• Pheochromocytoma
• Metastatic neoplasm
• Diabetes mellitus
• Premenopausal state

Investigations:

Bloodwork

• TSH (low), T4 & T3 (elevated)
• Thyroid antibodies – can use to differentiate Graves’ and toxic multinodular goiter

Imaging

• RAIU
  • Increased uptake in overactive thyroid, decreased in thyroiditis and iatrogenic T4 ingestion
  • Uptake is homogeneous in Graves’, heterogeneous in multinodular goiter, and single focus in a hot nodule

Management

ANTITHYROID DRUGS:

• Thionamides
  • Propylthiouracil (PTU) and Methimazole (Tapazole
    • Inhibit thyroid hormone synthesis (block thyroid peroxidase); inhibit peripheral conversion of T4 to T3
    • Most useful in young, nonpregnant patients with small glands and mild disease
    • Patients should be seen every 1 – 3 months until euthyroid, then q 3-4mo while remaining on medication
• B-BLOCKERS – Propranolol for symptomatic control

MEDICAL ABLATION

• Radioactive iodine – used in Graves’ when PTU or MMI fail to produce remission
• Usually require lifelong thyroid hormone replacement

SURGICAL ABLATION:

• Subtotal thyroidectomy