Thyrotoxicosis

Thyrotoxicosis 

Updated: 01/13/2021

© Jun Wang, MD, PhD

General features
  • Hypermetabolic state due to elevated circulating free T3 and T4
  • Associated with hyperactivity of thyroid gland, inappropriate release of thyroid hormones due to follicular damage, etc
  • Three most common causes
Diffuse hyperplasia associated with Graves disease
Terms
  • Hyperthyroidism: Status of thyroid hormone overproduction, may be clinically subtle, such as apathetic hyperthyroidism
  • Thyrotoxicosis: Clinical presentations caused by excess circulating thyroid hormone
  • Thyroid storm: Acute life threatening exacerbation of thyrotoxicosis
Etiology
  • Primary hyperthyroidism
Diffuse hyperplasia (such as Graves disease )
Hyperfunctional adenoma
Iodine-induced hyperthyroidism
Neonatal hyperthyroidism associated with maternal Graves disease
  • Secondary hyperthyroidism, rare
TSH producing pituitary tumor
  • Not associated with thyroid hyperfunction
Thyroiditis
Exogenous thyroxine intake
Clinical presentations
  • Symptoms: Hyperactivity, nervousness, anxiety, heat intolerance, etc
  • General signs: Tachycardia, arrhythmia, thyroid ocular changes, weight loss, etc
  • Thyroid signs: Enlargement, thyroid bruit
Thyroid oculopathy
  • Lid retraction
  • Lid lag on downward gaze
  • “Stare”
  • Edema of lids
  • Proptosis: only in Graves disease
Key laboratory findings
  • Low TSH, usually first positive finding
  • High thyroxin or FTI
  • If normal T4 or FTI, mild or subclinical
Treatment
  • Antithyroid medications
  • Symptom relief (rehydration, b-blockers, saline eye drops, surgery for ophthalmopathy, etc)


Back to thyroid pathology
Back to pathology of endocrine system
Back to contents

Comments

Popular posts from this blog

Contents

Anemia

Lymphoid neoplasms