Can Hashimoto's thyroiditis cause an elevated erythrocyte sedimentation rate (ESR)?

Can Hashimoto's Thyroiditis Cause an Elevated Erythrocyte Sedimentation Rate (ESR)?

Yes, Hashimoto's thyroiditis can cause an elevated erythrocyte sedimentation rate (ESR), as it is associated with a low-grade systemic inflammatory response even in euthyroid patients. 1

Evidence for Elevated ESR in Hashimoto's Thyroiditis

Hashimoto's thyroiditis (HT) is an autoimmune disorder characterized by lymphocytic infiltration of the thyroid gland and elevated levels of anti-thyroid antibodies. While traditionally viewed as a localized thyroid condition, recent evidence suggests it may represent a systemic inflammatory disorder.

Research findings supporting elevated ESR in Hashimoto's thyroiditis:

• A study specifically examining acute-phase reactants in Hashimoto's thyroiditis found that mean ESR was significantly higher in HT patients compared to control groups (p=0.024) 1
• The same study demonstrated elevated levels of other inflammatory markers including fibrinogen and serum amyloid A (SAA) in euthyroid HT patients 1
• This suggests a low-grade systemic inflammation exists in HT patients even when they are euthyroid

Clinical Relevance and Diagnostic Considerations

When evaluating elevated ESR in patients with suspected or confirmed Hashimoto's thyroiditis:

1. Differential diagnosis is important: Multiple guidelines list elevated ESR as a common finding in various inflammatory conditions:

   • Autoimmune diseases like systemic lupus erythematosus 2
   • Vasculitis 2
   • Polymyalgia rheumatica 2
   • Adult-onset Still's disease 2

2. Laboratory evaluation: When encountering elevated ESR in a patient with thyroid symptoms:

   • Check thyroid function tests (TSH, free T4) 2
   • Test for thyroid autoantibodies (anti-TPO, anti-thyroglobulin)
   • Consider additional inflammatory markers like CRP

3. Diagnostic value: While elevated ESR can occur in Hashimoto's thyroiditis, it's important to note:

   • The elevation is typically mild to moderate
   • In cases of very high ESR or severe thyroid pain, consider other diagnoses like subacute thyroiditis 3, 4
   • Laboratory features that help distinguish painful Hashimoto's from subacute thyroiditis include normal ESR (in some cases), significant radioactive iodine uptake, and significant antithyroid antibody titers 4

Additional Inflammatory Markers in Hashimoto's Thyroiditis

Beyond ESR, other inflammatory markers may be elevated in Hashimoto's thyroiditis:

• Neutrophil-to-lymphocyte ratio (NLR) has been found to be significantly higher in HT patients compared to controls 5
• Uric acid to HDL ratio (UHR) is elevated in HT patients and correlates with TSH levels 6
• C-reactive protein (CRP) may also be elevated in some patients with HT 1

Clinical Implications

The presence of elevated inflammatory markers in Hashimoto's thyroiditis has several implications:

1. Monitoring disease activity: ESR might serve as a marker of disease activity or inflammation in HT
2. Systemic nature: Supports the concept that HT is not merely a localized thyroid disorder but has systemic inflammatory effects
3. Differential diagnosis: In patients presenting with elevated ESR and thyroid symptoms, Hashimoto's thyroiditis should be considered in the differential diagnosis

Conclusion

While not universally elevated in all patients with Hashimoto's thyroiditis, ESR can indeed be increased due to the underlying autoimmune inflammatory process. This finding supports the growing recognition of Hashimoto's thyroiditis as a condition with systemic inflammatory effects beyond the thyroid gland itself.