What is the management approach for a patient with subacute thyroiditis, characterized by a painful thyroid nodule?

Management of Subacute Thyroiditis

For subacute thyroiditis presenting with a painful thyroid, initiate corticosteroids (prednisolone 20-48 mg daily) as first-line therapy rather than NSAIDs, as steroids provide faster symptom relief, reduce risk of permanent hypothyroidism, and achieve complete remission within two weeks. 1, 2

Initial Diagnostic Confirmation

Before initiating treatment, confirm the diagnosis with:

• Elevated ESR (typically >30 mm/h, often >50 mm/h) 1, 2
• Thyroid function tests showing initial hyperthyroidism (low TSH, elevated free T4) 3, 4
• Thyroid scintigraphy demonstrating low uptake if diagnosis is uncertain 5, 4
• Ultrasound showing focal or multifocal heterogeneous, hypoechoic, ill-defined areas with low vascularization 5, 4

Critical pitfall: Subacute thyroiditis can mimic a suspicious thyroid nodule on ultrasound, potentially leading to unnecessary surgery. The key distinguishing features are the clinical presentation of pain, elevated ESR, and low uptake on scintigraphy. 5, 4

Treatment Algorithm

First-Line: Corticosteroid Therapy

Prednisolone dosing:

• Starting dose: 20-48 mg daily 1, 2
• Duration: Taper over 4-6 weeks 2, 3
• Response timeline: Complete pain relief in 94% of patients within 2 weeks, with symptomatic remission achieved in all patients within 2 weeks 2

Why steroids over NSAIDs:

• NSAIDs (ibuprofen 1800 mg daily) fail to provide adequate clinical response in 59.5% of patients at first follow-up, requiring treatment change to steroids in 54% of cases within 9.5 days 1
• Permanent hypothyroidism develops in 22.8% of NSAID-only patients versus 6.6% of steroid-only patients 1
• Steroid treatment is a protective factor against permanent hypothyroidism (p=0.039) 1

Adjunctive Symptomatic Management

• Beta-blockers (atenolol or propranolol) for adrenergic symptoms during the hyperthyroid phase 6, 3
• Analgesics as needed for breakthrough pain 6

When to Consider NSAIDs

NSAIDs may be reserved for:

• Very mild cases with minimal pain
• Patients with contraindications to corticosteroids
• However, be aware: NSAID-only treatment carries higher recurrence rates (10.5% vs 23% with steroids, though this difference favors NSAIDs) and significantly higher permanent hypothyroidism risk 1

High-Risk Patients Requiring Aggressive Treatment

Positive anti-TPO antibodies is the strongest predictor of permanent hypothyroidism (p=0.029), making early corticosteroid therapy particularly important in these patients 1

Monitoring Protocol

Acute Phase (First 4-6 Weeks)

• Monitor thyroid function every 2-3 weeks to detect transition from hyperthyroidism to hypothyroidism 6
• Check ESR at 2 and 4 weeks (should normalize from mean 57 mm/h to 17 mm/h by 4 weeks) 2
• Assess pain relief at 2 weeks (should be complete or significantly improved) 2

Triphasic Disease Pattern

Subacute thyroiditis follows a predictable course:

1. Hyperthyroid phase (initial weeks): Release of preformed thyroid hormone from damaged cells 3
2. Hypothyroid phase (weeks to months): Depletion of thyroid stores 3
3. Recovery phase (months): Restoration of normal function in most patients 3

Long-Term Follow-Up

• Continue monitoring for 12 months after resolution to detect permanent hypothyroidism (develops in 6.6-22.8% depending on treatment) 1
• Elevated TSH during recovery may be transient; in asymptomatic patients with normal free T4, monitor for 3-4 weeks before treating to determine if spontaneous recovery occurs 6

Treatment of Hypothyroid Phase

If symptomatic hypothyroidism develops:

• Patients <70 years without cardiac disease: Full replacement levothyroxine ~1.6 mcg/kg/day 6
• Patients >70 years or with cardiac disease: Start low (25-50 mcg) and titrate up 6
• Monitor for recovery: Some patients recover thyroid function; if TSH becomes low on therapy, reduce or discontinue levothyroxine with close follow-up 6

Recurrence Management

Overall recurrence rate is 19.8%, with higher rates in steroid-only patients (23%) versus NSAID-only patients (10.5%, p=0.04) 1

For recurrence: Reinitiate corticosteroids at previous effective dose and taper more gradually over 6-8 weeks 1, 3