MON-438 A Near Miss Case: Acute Infectious Thyroiditis in the Setting of Peritonsillar Abscess

Abstract Disclosure: R. Ozturk: None. A. Jain: None. J. Bou Saba: None. Z. He: None. Introduction: Infectious thyroiditis is a rare condition but can potentially be fatal. Early recognition and implantation of appropriate imaging studies are key to achieve favorable outcomes. We present an acute infective thyroiditis case that was initially considered to be subacute thyroiditis. Case Description: A 71-year-old male with a past medical history of type 2 diabetes mellitus and chronic kidney disease presented with a sore throat, fever, sensation of choking, and dysphagia. The next day, the patient's symptoms worsened to the point of only whispering, with associated trismus, anterior right-sided neck pain, and swelling with difficulty swallowing oral secretions. CT head and neck without contrast revealed a right-sided peritonsillar abscess. Incision and drainage were unsuccessful in aspirating any drainage. The patient was started on high-dose IV Dexamethasone and antibiotics. He developed atrial fibrillation with rapid ventricular response and was noted to have severe tenderness on thyroid exam. Despite normal thyroid function test results from 3 days prior, the thyroid function tests were repeated. Results showed that TSH was 0.06 uIU/mL (0.34-5.60), elevated free T4 1.79 ng/d (0.93 -1.70). Inflammatory markers ESR and C Reactive Protein were both significantly elevated. Although a repeat CT showed potential spread of infection in anterior neck with normal appearance of thyroid, a thyroid ultrasound showed complex fluid collections situated at the anteromedial aspect of the right thyroid gland and anterior aspect of the left thyroid gland. Multiple incision and drainages of deep neck abscesses were performed bilaterally by ENT. Since then, the patient has significantly improved. An outpatient ultrasound examination done one month after the hospitalization revealed a normal thyroid gland without any fluid collection. Thyroid function was also normal. Conclusion: We present here a case of acute suppurative thyroiditis extending from peritonsillar infection. The thyroid ultrasound revealed the abscess although the neck CT did not report any abnormality in thyroid gland. This condition was almost missed and patient outcome would have been grave if the thyroid function tests had not been repeated and the thyroid ultrasound had not been performed on time. Presentation: Monday, July 14, 2025