Life-threatening airway obstruction by Riedel's thyroiditis: a rare presentation and diagnostic dilemma.

Summary: Riedel's thyroiditis is the rarest form of thyroiditis, occasionally resulting in rapid thyroid enlargement and potential tracheal obstruction. Here, we detail the case of an 81-year-old woman with a medical history including Hodgkin lymphoma, Hashimoto's thyroiditis, and multinodular goiter. She presented to the emergency room with stridor, cervical swelling, and breathing difficulties for over 2 days. CT scans revealed substantial thyroid enlargement causing significant glottal and tracheal compression, to a minimum tracheal diameter of 7 mm. Due to the severity of the compressive symptoms, orotracheal intubation and mechanical ventilation were deemed necessary. Surprisingly, despite the initial suspicion of malignancy given the rapid growth in the elderly, subsequent cytological and histological evaluations indicated a benign form of invasive fibrous thyroiditis - Riedel's thyroiditis. Although surgical intervention was advised, the patient declined and opted for endobronchial treatment with a prosthetic stent and subsequent treatment with systemic glucocorticoids. Following successful treatment, she was discharged within a week and resumed normal activities without respiratory distress. This case is noteworthy for its rapid benign mass growth, rare emergent presentation, and the patient's advanced age.

Learning points: The rapid enlargement of the thyroid gland in elderly patients poses a diagnostic challenge, stemming from the higher occurrence of aggressive thyroid carcinomas. Despite the clinical presentation, a comprehensive diagnostic workup, including fine-needle aspiration and core-needle biopsy, is crucial for accurately distinguishing between benign and malignant causes of thyroid nodule enlargement. This case report illustrates diverse treatment options for Riedel's thyroiditis, and the importance of individualized treatment plans based on the degree of airway obstruction, patient preferences, and response to initial interventions. Clinicians should contemplate the inclusion of glucocorticoids in the therapeutic regimen for Riedel's thyroiditis, particularly in cases where surgical intervention is not feasible or declined by the patient.