Etiologic agents include S aureus and oropharyngeal flora Appropriate broadspectrum parenteral antimicrobial therapy is usually sufficient to eradicate the infection Abscess formation necessitates incision and drainage by a surgeon comfortable with thyroid anatomy Evaluation with a CT or esophagography should be performed to improve identification of a pyriform sinus fistula If present, the fistula will often require excision after resolution of the acute infection in order to prevent recurrences Acute immune stimulation of the thyroid gland may also produce diffuse thyroid enlargement In Graves disease , autoantibody attachment to the thyrotropin receptor stimulates an increase in thyroid hormone synthesis and release Patients may initially have a history of changes of behavior, decrease in school performance, and/or increase in linear growth On presentation, patients will have a symmetrically enlarged smooth nontender goiter and may have signs of thyrotoxicosis, including tachycardia, nervousness, tremor, hypertension, exophthalmos, and increased appetite A thyroid bruit may be auscultated in 50% of patients An elevated free T4 in the context of a low TSH level and presence of TSH receptor antibodies confirms the diagnosis Consultation with a pediatric endocrinologist is indicated with initial focus on managing the symptoms of hyperthyroidism or thyrotoxicosis, if present Thyroid nodules are present in up to 2% of children, and deserve careful attention Although most are secondary to chronic lymphocytic thyroiditis or consist of a benign adenoma, the incidence of malignant neoplasms is actually higher in children with thyroid nodules than in adults Hence, every thyroid nodule found in a child merits a complete evaluation In the ED, this evaluation should include thyroid function tests and neck ultrasound Urgent outpatient follow-up with a specialist with expertise in the evaluation of thyroid nodules is required to facilitate additional testing including ultrasound-guided fine-needle aspiration and genetic testing Lateral Neck Lesions Enlarged cervical lymph nodes constitute the most common lateral neck masses in children Knowledge of the anatomy of the cervical lymphatics is of fundamental importance to understanding processes that cause enlargement of cervical lymph nodes This section focuses mainly on local processes that cause nodal enlargement, but it is important to note that many systemic infections, inflammatory disorders, and malignancy can cause diffuse adenopathy that includes the cervical chain (see Chapter 47 Lymphadenopathy ) Therefore, any