Endocrine Abstracts

JOINT4027

Introduction: In adults, thyroid autonomous adenomas causing hyperthyroidism are relatively common and are mostly due to mutations that increase the structural activity of the thyroid-stimulating hormone receptor (TSHR). However, in children with hyperthyroidism, autonomous adenomas are exceptional, and reports on their clinical and molecular characteristics are scarce. In this report, a case of an autonomous hot thyroid nodule is presented, and its management is shared. Case Report:A 14-year-and-9-month-old female patient presented with swelling in the neck. It was learned that the patient had complaints of hair loss for the last 3–4 months but no complaints of palpitations, weight loss, or hand tremors. Her personal and family history revealed that she was born at term via cesarean section with a birth weight of 3040 g. On physical examination, her height was 177.2 cm (2.71 SDS), weight was 86 kg (3.59 SDS), body mass index (BMI) was 27.3 kg/m² (2 SDS), blood pressure was 110/70 mmHg, and pulse was 88 bpm.A 3x3 cm palpable mass was detected in the left thyroid lobe. Pubertal development was at Tanner stage 5, and other systemic examinations were normal. Thyroid function tests showed free T4 (sT4): 1.84 ng/dl (0.98-1.63), free T3 (sT3): 7.15 ng/l (2.56-5), and thyroid-stimulating hormone (TSH): <0.005 mIU/l (0.51-4.3). Anti-thyroid peroxidase antibody, anti-thyroglobulin antibody, and TSH receptor antibody were negative. Thyroid ultrasonography (USG): Right lobe: 50x19x14 mm (6.65 mL) Left lobe: 50x25x32 mm (20 mL) Total volume: 9.6 SDS.A well-defined, approximately 35x30x24 mm semisolid nodule with cystic components, a hypoechoic halo, and internal vascularity detected by color Doppler ultrasonography was observed, almost completely covering the left lobe. Thyroid scintigraphy showed a hyperactive nodular area in the left lobe (Figure 1). The patient was started on propranolol and low-dose methimazole. Based on clinical, laboratory, and imaging findings, the patient was diagnosed with an autonomously functioning hot nodule. To rule out malignancy, a fine-needle aspiration biopsy (FNAB) was performed, and the nodule was reported as benign. The patient was referred to pediatric surgery, and after achieving a euthyroid state, left lobectomy was performed. The lobectomy pathology report indicated nodular hyperplasia. Postoperatively, all treatments were discontinued.A TSHR gene analysis was planned to investigate the etiology.

Conclusion: In cases of hot nodules causing hyperthyroidism, surgical removal is recommended after achieving a euthyroid state with antithyroid treatment. Studies have reported that hot nodules in children have a higher malignancy risk, with 2-18% of these nodules being malignant. In this report, the management of a case with a hot thyroid nodule was discussed.