Endocrine · Year 2 · from Endocrine
Case 1: Graves Disease
Patient Demographics
- Age: 34 years
- Sex: Female
- Occupation: Marketing manager
Chief Complaint
"I've lost 15 pounds without trying, my heart races all the time, and I can't tolerate the heat."
History of Present Illness
A 34-year-old woman presents with a 4-month history of unintentional weight loss despite increased appetite, palpitations, heat intolerance, and excessive sweating. She reports feeling anxious, irritable, and has noticed tremor in her hands. She has difficulty sleeping and feels fatigued despite sleeping 8 hours. Her menstrual periods have become lighter and irregular. Her colleagues have commented that her eyes appear more prominent. She has a family history of thyroid disease (mother with Hashimoto's thyroiditis).
Physical Examination
- Vital Signs: BP 138/62 mmHg (widened pulse pressure), HR 108 bpm (regular), Temp 37.3°C
- General: Anxious, fidgety, thin-appearing woman
- Eyes: Bilateral proptosis (exophthalmos), lid retraction, lid lag, conjunctival injection
- Neck:
- Diffusely enlarged thyroid gland (2x normal)
- Non-tender, smooth texture
- Thyroid bruit audible
- Cardiovascular: Tachycardia, hyperdynamic precordium
- Extremities: Fine tremor with arms extended, warm and moist palms
- Skin: Warm, moist, pretibial myxedema (waxy, non-pitting plaques on anterior shins)
- Reflexes: Hyperactive with rapid relaxation phase
Workup
- Laboratory Studies:
- TSH: <0.01 mIU/L (suppressed)
- Free T4: 4.8 ng/dL (elevated, normal 0.9-1.7)
- Free T3: 12.6 pg/mL (elevated, normal 2.3-4.2)
- TSH receptor antibodies (TRAb/TSI): Strongly positive
- Anti-TPO antibodies: Positive
- Thyroid Uptake and Scan: Diffusely increased uptake (45%, normal 10-30%), homogeneous uptake
- ECG: Sinus tachycardia
Diagnosis
Graves disease with:
- Hyperthyroidism
- Graves ophthalmopathy (orbitopathy)
- Pretibial myxedema (dermopathy)
Treatment
- Symptomatic relief:
- Beta-blocker (propranolol 20-40 mg TID) for tachycardia, tremor, anxiety
- Definitive treatment options:
- Antithyroid drugs (ATDs):
- Methimazole 10-20 mg daily (preferred) OR
- Propylthiouracil (PTU) 100 mg TID (preferred in 1st trimester pregnancy)
- Trial for 12-18 months; ~30-50% remission rate
- Radioactive iodine (I-131):
- Preferred in US for definitive treatment
- Results in hypothyroidism (intentional)
- Thyroidectomy:
- For large goiter, suspicious nodules, or patient preference
- Ophthalmopathy management:
- Lubricating eye drops
- Smoking cessation (critical)
- Glucocorticoids for moderate-severe disease
- Orbital decompression for severe cases
- Teprotumumab (IGF-1R inhibitor) for moderate-severe active disease
- Monitoring: TSH, free T4 every 4-6 weeks until stable
Clinical Pearl
Graves disease is an autoimmune condition caused by TSH receptor-stimulating antibodies (TSI) that mimic TSH action. It is the most common cause of hyperthyroidism in iodine-sufficient regions. The classic triad of Graves disease is hyperthyroidism, ophthalmopathy, and dermopathy, though not all patients have all three features. Ophthalmopathy can worsen after radioactive iodine treatment, especially in smokers; this can be prevented with glucocorticoid prophylaxis in high-risk patients. Methimazole is preferred over PTU except in first trimester pregnancy (PTU) and thyroid storm (PTU blocks peripheral T4→T3 conversion).
Clinical Image
Bilateral exophthalmos (proptosis) characteristic of Graves ophthalmopathy, showing lid retraction and scleral show.
Image Source: Wikimedia Commons - "Graves disease ophthalmopathy" License: CC BY-SA 3.0 URL: https://commons.wikimedia.org/wiki/File:Proptosis_and_lid_retraction_from_Graves%27_Disease.jpg