# Clinical Cases: Thyroid Disorders

## Case 1: Graves Disease with Thyroid Storm

### Patient Demographics
- **Age:** 34 years
- **Sex:** Female
- **Occupation:** Marketing executive

### Chief Complaint
"I have a high fever, my heart is racing, and I feel like I'm going crazy."

### History of Present Illness
The patient presents to the emergency department with fever, palpitations, and agitation. She reports a 3-month history of unintentional weight loss (15 pounds), heat intolerance, and tremors. Over the past week, she developed an upper respiratory infection with cough and sore throat. Today she awoke with severe palpitations, drenching sweats, high fever, and extreme anxiety. Her husband notes she has been increasingly confused and agitated throughout the day. Past medical history includes a diagnosis of hyperthyroidism 2 years ago for which she was prescribed methimazole, but she stopped taking it 6 months ago because she "felt fine."

### Vital Signs
- Temperature: 104.2 degrees F (40.1 degrees C)
- Blood pressure: 168/72 mmHg (widened pulse pressure)
- Heart rate: 156 bpm, irregularly irregular
- Respiratory rate: 26/min
- Oxygen saturation: 94% on room air

### Physical Examination
**General:** Diaphoretic, agitated, restless, unable to sit still
**HEENT:** Lid lag, exophthalmos bilateral, moist mucous membranes
**Neck:** Diffusely enlarged thyroid gland (goiter), non-tender, audible bruit over thyroid
**Cardiovascular:** Tachycardic, irregularly irregular (atrial fibrillation), hyperdynamic precordium, systolic flow murmur
**Pulmonary:** Tachypneic, clear to auscultation
**Extremities:** Fine tremor of outstretched hands, warm and moist skin, pretibial myxedema
**Neurologic:** Hyperreflexic, agitated, difficulty following commands, intermittently confused

### Laboratory Findings
- TSH: < 0.01 mIU/L (suppressed)
- Free T4: 7.8 ng/dL (markedly elevated, normal 0.8-1.8)
- Free T3: 18.2 pg/mL (markedly elevated, normal 2.3-4.2)
- Thyroid stimulating immunoglobulin (TSI): Positive
- WBC: 14,200/mcL
- AST: 86 U/L
- ALT: 78 U/L
- Glucose: 186 mg/dL
- Calcium: 11.2 mg/dL

### Electrocardiogram
- Atrial fibrillation with rapid ventricular response, rate 156 bpm
- No ST-T wave changes

### Burch-Wartofsky Point Scale (BWPS) for Thyroid Storm
- Temperature 104.2 F (40.1 C): 25 points
- Heart rate >140: 25 points
- Atrial fibrillation: 10 points
- Moderate agitation: 10 points
- Mild hepatic dysfunction: 0 points
- Precipitant present (infection): 10 points
- **Total: 80 points (>45 suggests thyroid storm)**

### Diagnosis
**Thyroid storm** secondary to Graves disease, precipitated by infection and medication non-compliance

### Management
**Step 1 - Block thyroid hormone synthesis:**
1. Propylthiouracil (PTU) 500-1000 mg PO/NG loading dose, then 250 mg every 4 hours
   - PTU preferred over methimazole in thyroid storm because it also blocks peripheral T4 to T3 conversion

**Step 2 - Block thyroid hormone release (given 1 hour AFTER PTU):**
2. Potassium iodide (SSKI) 5 drops every 6 hours OR Lugol's solution 10 drops every 8 hours
   - Must wait 1 hour after PTU to prevent iodide from being used as substrate for new hormone synthesis (Wolff-Chaikoff effect)

**Step 3 - Block peripheral effects and T4 to T3 conversion:**
3. Propranolol 60-80 mg PO every 4 hours (or IV if unable to take PO)
   - Controls tachycardia, tremor, and blocks peripheral conversion
4. Esmolol IV infusion if rapid control needed

**Step 4 - Glucocorticoids:**
5. Hydrocortisone 300 mg IV loading dose, then 100 mg IV every 8 hours
   - Blocks peripheral T4 to T3 conversion
   - Provides adrenal support (thyroid storm increases cortisol metabolism)

**Step 5 - Supportive care:**
6. Active cooling with cooling blankets and acetaminophen
   - AVOID aspirin (displaces T4 from binding proteins, increasing free hormone)
7. IV fluids for dehydration
8. Treat precipitating cause (antibiotics for infection)
9. ICU admission for monitoring
10. Rate control for atrial fibrillation (may require digoxin in addition to beta-blocker)

### Clinical Pearl
Thyroid storm is a clinical diagnosis - there is no laboratory value that distinguishes it from uncomplicated thyrotoxicosis. The Burch-Wartofsky Point Scale helps quantify the probability but clinical judgment remains paramount. The treatment follows a logical sequence: first block new hormone synthesis (PTU), then block hormone release (iodine - but only after synthesis is blocked), then block peripheral effects (beta-blocker and steroids). This patient demonstrates the typical precipitant pattern: a patient with underlying uncontrolled Graves disease who develops an acute stressor (infection) that tips them into the decompensated state of thyroid storm.

### Clinical Image
![Thyroid Goiter](case_01_image.jpg)

**Image Description:** Clinical photograph demonstrating diffuse enlargement of the thyroid gland (goiter) characteristic of Graves disease. The enlarged thyroid may be visible as a fullness in the anterior neck.

**Attribution:** Image from Wikimedia Commons, by Michael Starks. Licensed under CC BY-SA 3.0. Source: https://commons.wikimedia.org/wiki/File:Goitre_-_Teknaf%2C_Bangladesh.jpg

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## Case 2: Myxedema Coma

### Patient Demographics
- **Age:** 76 years
- **Sex:** Female
- **Occupation:** Retired nurse

### Chief Complaint
Found unresponsive at home by her daughter.

### History of Present Illness
The patient was found unresponsive in her home by her daughter who came to check on her after not hearing from her for 2 days. The home was very cold as the heating had malfunctioned. The daughter reports that her mother has a history of hypothyroidism diagnosed 15 years ago and was on levothyroxine, but she ran out of medication approximately 2 months ago and did not refill it due to financial difficulties. Over the past several weeks, the patient had become increasingly fatigued, constipated, and "slow in her thinking" according to family members. The daughter last spoke with her 3 days ago when she was complaining of a "cold" with cough and congestion.

### Vital Signs
- Temperature: 93.2 degrees F (34.0 degrees C) - hypothermia
- Blood pressure: 84/58 mmHg - hypotension
- Heart rate: 42 bpm - bradycardia
- Respiratory rate: 8/min - hypoventilation
- Oxygen saturation: 86% on room air

### Physical Examination
**General:** Obtunded, responds only to painful stimuli, non-pitting edema of face and extremities (myxedema)
**HEENT:** Periorbital edema, macroglossia, coarse dry hair, lateral eyebrow thinning
**Neck:** Thyroidectomy scar noted, no palpable thyroid tissue
**Cardiovascular:** Bradycardic, distant heart sounds, no murmurs, JVP difficult to assess
**Pulmonary:** Shallow respirations, decreased breath sounds at bases, dullness to percussion bilaterally
**Abdomen:** Distended, hypoactive bowel sounds
**Extremities:** Non-pitting edema, delayed relaxation of deep tendon reflexes, cool dry skin
**Neurologic:** GCS 7 (E1V2M4), responds only to painful stimuli

### Laboratory Findings
- TSH: 127 mIU/L (markedly elevated)
- Free T4: < 0.1 ng/dL (undetectable)
- Free T3: < 0.5 pg/mL (undetectable)
- Sodium: 118 mEq/L (low - hyponatremia)
- Glucose: 52 mg/dL (low - hypoglycemia)
- Cortisol (random): 8 mcg/dL (low-normal, inadequate for stress)
- ABG: pH 7.28, PaCO2 58 mmHg, PaO2 54 mmHg (respiratory acidosis with hypoxemia)
- CPK: 2,840 U/L (elevated)
- Hemoglobin: 9.8 g/dL (anemia)

### Chest X-ray
- Bilateral pleural effusions
- Enlarged cardiac silhouette (pericardial effusion versus cardiomegaly)

### Diagnosis
**Myxedema coma** secondary to severe hypothyroidism from medication non-adherence, precipitated by cold exposure and presumed respiratory infection

### Management
**Airway and breathing:**
1. Endotracheal intubation for airway protection and respiratory failure
2. Mechanical ventilation with careful attention to avoid hyperventilation

**Thyroid hormone replacement:**
3. IV levothyroxine (T4) 200-500 mcg loading dose (use lower end of range given age and cardiac risk)
4. Continue IV levothyroxine 50-100 mcg daily until able to take PO
5. Consider adding IV liothyronine (T3) 5-20 mcg every 8 hours for faster onset (controversial)

**Glucocorticoid coverage:**
6. Hydrocortisone 100 mg IV every 8 hours
   - MUST give before or with thyroid hormone to prevent precipitating adrenal crisis
   - Thyroid hormone replacement increases cortisol metabolism
   - Can discontinue after adrenal insufficiency is excluded by cosyntropin stimulation test

**Supportive care:**
7. Passive rewarming with blankets (avoid active external warming which causes vasodilation and cardiovascular collapse)
8. IV dextrose for hypoglycemia
9. Careful IV fluid resuscitation (these patients have impaired free water excretion)
10. Treat precipitating infection with broad-spectrum antibiotics
11. ICU admission with continuous cardiac monitoring

**Avoid:**
- Sedatives and opioids (impair already depressed respiration)
- Active external warming
- Rapid fluid resuscitation (risk of fluid overload with cardiac dysfunction)

### Clinical Pearl
Myxedema coma represents the most severe manifestation of hypothyroidism and carries a mortality rate of 30-60% even with treatment. The hallmark clinical triad is hypothermia, altered mental status, and a precipitating event (often infection or cold exposure). Unlike its name suggests, true coma is not required for diagnosis - any degree of altered mentation in the setting of severe hypothyroidism should trigger concern. The most critical management principle is that glucocorticoids MUST be administered before or concurrent with thyroid hormone replacement, as thyroid hormone increases cortisol metabolism and can precipitate adrenal crisis in patients with subclinical adrenal insufficiency.

### Clinical Image
![Thyroid Disease](case_01_image.jpg)

**Image Description:** Clinical photograph demonstrating features of thyroid disease affecting the neck region. In myxedema coma, patients may show non-pitting edema of the face and extremities, but the thyroid gland itself may be atrophic (as in Hashimoto's thyroiditis) or absent (post-thyroidectomy).

**Attribution:** Image from Wikimedia Commons, by Michael Starks. Licensed under CC BY-SA 3.0. Source: https://commons.wikimedia.org/wiki/File:Goitre_-_Teknaf%2C_Bangladesh.jpg

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