6575 From Tonsils to the Thyroid: A Rare Case of Acute Suppurative Thyroiditis in an Immunocompetent Adult

Abstract Disclosure: F. Sajid: None. A. Mubashir: None. F. Mohsin: None. M. Sattar: None. Introduction: Acute suppurative thyroiditis (AST) is a rare infection of the thyroid gland due to its high vascularity, protective encapsulation, and high iodine content. Most AST cases occur in children with anatomical aberrations or in immunosuppressed adults. Here, we describe a case of AST in an immunocompetent woman. Case: A 54-year-old woman with no medical history presented to the emergency department due to dyspnea, dysphagia, and odynophagia for two days. She reported a four-day history of sore throat, fever, and chills. She was saturating well on room air but was sitting in a tripod position. She had erythema, swelling, tenderness to palpation in the anterior neck with a hoarse voice, and moderate trismus. Nasopharyngoscopy revealed no mass, but the scope could not pass beyond the velum due to edema. The patient’s condition quickly deteriorated, necessitating emergent intubation for acute hypoxic respiratory failure. After intubation, the patient had cardiac arrest with asystole requiring resuscitation and successful ROSC. The initial CT scan showed extensive soft tissue abnormalities in the nasopharynx and parapharyngeal tissues, extending to the thyroid gland and mediastinum with the possibility of developing abscesses. A thyroid ultrasound showed a heterogeneous thyroid gland without nodules or increased vascularity. Treatment commenced with ampicillin-sulbactam. Laboratory results showed Free T4 of 4.74 ng/dL (0.58-1.64), TSH 0.03 MCIU/mL (0.39-4.08), Total T3 1.56 ng/dL (0.72-1.35), WBC 19.3 K/UL (4.8-10.8), and elevated ESR and CRP levels. Thyroid-stimulating Immunoglobulin (TSI), Thyroid Peroxidase (TPO) Antibody, and Thyrotropin Binding Inhibitory Immunoglobulin (TBII) were negative, making AST the top differential. Methimazole was initiated due to concerns of thyroid storm, but it was quickly tapered due to a significant decrease in Free T4 levels and suspicion of AST. A repeat CT scan revealed more defined abscesses along the bilateral pharyngeal walls extending to the thyroid bed. The patient underwent bilateral tonsillectomy and drainage of the abscesses. She was extubated the following day. Cultures from the abscesses grew rare Klebsiella pneumoniae, susceptible to Ampicillin-sulbactam. A barium swallow on day 14 showed no evidence of a pyriform sinus fistula. She was discharged on day 15 with Augmentin for 7 days. On discharge, free T4 decreased to half (2.39 ng/dL), and Total T3 normalized (1.08ng/dL). Conclusion: This case presents a rare instance of AST in an immunocompetent patient without anatomical anomalies, stemming from the spread of peritonsillar and parapharyngeal abscesses into the thyroid bed. AST should be considered in cases of deep neck infections, as it is a potentially life-threatening disease. It is crucial to identify and treat AST early to prevent complications. The primary treatment involves antibiotics, incision, and drainage. Presentation: 6/1/2024