[Thyroid echography in chronic autoimmune lymphocytic thyroiditis]

Area of Science:

• Endocrinology
• Radiology
• Immunology

Background:

• Cervical echotomography is routinely used in thyroid investigations.
• A diffused microechoic thyroid parenchyma pattern is observed in various thyroid conditions, including Graves' disease, subacute thyroiditis, and chronic lymphocytic thyroiditis (LCT).
• Distinguishing between these conditions can be challenging based solely on imaging.

Purpose of the Study:

• To evaluate the diagnostic value of a diffused microechoic thyroid parenchyma pattern in chronic lymphocytic thyroiditis (LCT).
• To assess the utility of this sonographic finding in differentiating LCT from other thyroid pathologies.

Main Methods:

• Systematic cervical echotomography was performed on patients undergoing thyroid investigation.
• The study focused on 48 cases with a distinct diffused microechoic thyroid parenchyma.
• Graves' disease and subacute thyroiditis were excluded using clinical and biological data; LCT diagnosis was confirmed by antithyroid antibodies or clinical probability.

Main Results:

• In 31 of 48 cases, LCT was clinically and biologically confirmed, often with elevated antithyroid antibodies.
• In the remaining 17 cases, LCT was the most probable diagnosis despite insufficient autoimmune evidence.
• The diffused microechoic pattern was consistently observed in these LCT cases.

Conclusions:

• The diffused microechoic character of the thyroid parenchyma, while not specific, is a significant finding.
• This echographic sign is valuable for supporting the diagnosis of chronic lymphocytic thyroiditis (LCT).
• Further autoimmune testing may be necessary when this pattern is observed without clear serological evidence of LCT.