DOI: https://doi.org/10.36347/sasjm.2026.v12i03.006

Pages: 188-191

Background: The EU-TIRADS classification system is a cornerstone of thyroid nodule management, yet its specificity is limited by benign pathologies that mimic malignancy. Focal Hashimoto's thyroiditis can create inflammatory "pseudonodules" with high-risk sonographic features, leading to a EU-TIRADS 5 classification and potentially unnecessary invasive procedures. Case Presentation: A 45-year-old female with newly diagnosed hypothyroidism was found to have an 11 mm EU-TIRADS 4 nodule. A three-month follow-up ultrasound revealed progression to two markedly hypoechoic, irregular nodules classified as EU-TIRADS 5. Fine-needle aspiration cytology was discordant, yielding a benign (Bethesda II) result. A subsequent 6-month control ultrasound demonstrated complete resolution of the discrete nodules, which had coalesced into a focal, ill-defined hypoechoic plaque. Serological testing confirmed high titers of anti-thyroid peroxidase antibodies, establishing the diagnosis of focal Hashimoto’s thyroiditis. Conclusion: This case highlights the importance of integrating clinical context, serology, and imaging evolution in the assessment of suspicious thyroid nodules. In hypothyroid patients with EU-TIRADS 5 nodules that are discordant with benign cytology, short-term active surveillance is a critical problem-solving tool that can confirm an inflammatory etiology and prevent unnecessary intervention.