(i.e., Kawasaki disease) often have cervical lymphadenopathy and, on rare occasions, have active life-threatening vasculitis of the coronary vessels Although neck tumors generally grow outward, in children, they may become large enough to encroach on vital structures Lymphoma, an uncommon but important cause of neck mass, is usually associated with painless enlargement (often of supraclavicular nodes) that occurs over several weeks in the older school-aged children Anterior mediastinal node involvement creates airway collapse in the supine position secondary to tracheal compression This may manifest as orthopnea Cystic hygromas and hemangiomas occasionally enlarge sufficiently enough to interfere with feeding or to obstruct the airway Other neoplasms, such as rhabdomyosarcoma, leukemia, neuroblastoma, and histiocytosis X, are life threatening because of local invasion and metabolic and hematologic effects Table 48.1 lists disorders that constitute true emergencies because of local pressure on vital structures or because of systemic toxicity TABLE 48.1 LIFE-THREATENING CAUSES OF NECK MASS Hematoma secondary to trauma Cervical spine injury Vascular compromise or acute bleeding Late arteriovenous fistula Subcutaneous emphysema with associated airway or pulmonary injury Local hypersensitivity reaction (sting/bite) with airway edema Airway compromise with epiglottitis, peritonsillar abscess, or infection of floor of mouth or retropharyngeal space (with adenopathy) Bacteremia/sepsis associated with local infection of a cyst (cystic hygroma, thyroglossal, or branchial cleft cyst) Non-Hodgkin lymphoma with mediastinal mass and airway compromise Thyroid storm Mucocutaneous lymph node syndrome with coronary vasculitis (Kawasaki disease) Tumor—leukemia, lymphoma, rhabdomyosarcoma, histiocytosis X Lemierre syndrome Child With Neck Mass and No Distress Most children in the ED with a neck mass are not in distress; the leading diagnoses are reactive adenopathy or acute lymphadenitis from viral or bacterial infection A common concern, however, is deciding which neck mass bears the diagnosis of malignancy and requires biopsy or further evaluation Table 48.2 lists common nonemergent causes of neck mass History To facilitate differential diagnosis development, it is crucial to determine both the patient’s age when the mass was first noticed, as well as current symptom duration A neck mass presenting at several weeks of life may represent birth trauma with hemorrhage into the sternocleidomastoid and resulting torticollis Conversely, congenital cysts may not come to attention until they have enlarged with infection or inflammation, often increasing in size with recurrence Details of chronicity, size, progression, and evidence of inflammation (e.g., dimples, sinuses, drainage over time), can help to distinguish between infection and neoplasm Although longer duration is concerning for malignancy, the duration the “node” is present is not reliable in discriminating benign from malignant TABLE 48.2 COMMON CAUSES OF NECK MASS Lymphadenopathy secondary to viral or bacterial infection Cervical adenitis (bacterial) Hematoma Benign tumors—lipoma, keloid Congenital cyst (squamous epithelial cysts) TABLE 48.3 DIFFERENTIAL DIAGNOSIS OF NECK MASS BY ETIOLOGY Congenital Squamous epithelial cyst (congenital or posttraumatic) Pilomatrixoma (Malherbe calcifying epithelioma) Hemangioma and cystic hygroma (lymphangioma) Branchial cleft cyst Thyroglossal duct cyst Laryngocele Dermoid cyst Cervical rib Inflammatory Infection Cervical adenitis—streptococcal, staphylococcal, fungal, mycobacterial, cat-scratch disease, tularemia Adenopathy—secondary to local head and neck infection Secondary to systemic “infection”—infectious mononucleosis, Cytomegalovirus, toxoplasmosis, others Retropharyngeal abscess Focal myositis—inflammatory muscular pseudotumor Lemierre syndrome “Antigen” mediated Local hypersensitivity reaction (sting/bite) Serum sickness, autoimmune disease Pseudolymphoma (secondary to phenytoin) Mucocutaneous lymph node syndrome (Kawasaki disease) Sarcoidosis Caffey–Silverman syndrome Trauma Hematoma Sternocleidomastoid tumor of infancy (fibromatosis colli) Subcutaneous emphysema Acute bleeding Arteriovenous fistula Foreign body Cervical spine fracture Neoplasms Benign