What are the possible differential diagnoses for bilateral lower jaw/neck swelling in a 5-year-old child?

Differential Diagnosis of Bilateral Lower Jaw/Neck Swelling in a 5-Year-Old Child

The most common causes of bilateral lower jaw/neck swelling in a 5-year-old are infectious lymphadenitis (particularly from upper respiratory tract infections), parotitis, and deep neck infections, though malignancy including lymphoma must be systematically excluded. 1, 2, 3

Infectious Etiologies (Most Common in This Age Group)

Cervical Lymphadenitis

• Bilateral cervical lymphadenopathy is the most frequent cause of neck swelling in children, typically following upper respiratory tract infections (30.8% of cases) 2, 3
• Look for: fever (75% of cases), recent URI symptoms, mobile tender nodes, overlying skin warmth or erythema 3
• Staphylococcus aureus is the most commonly isolated pathogen when cultures are obtained 3

Parotitis

• Bilateral parotid swelling presents as swelling in the lower jaw/angle of mandible region 1
• Consider mumps (if unvaccinated), bacterial parotitis, or recurrent parotitis of childhood 1
• Look for: swelling anterior to ear/angle of jaw, pain with eating, Stensen's duct inflammation 1

Deep Neck Infections

• Parapharyngeal space infections (42.3% of deep neck infections) can present with bilateral neck swelling 3
• Submandibular space infections present with bilateral lower jaw swelling 3
• Look for: rapid onset, fever, neck mass/swelling (82.7%), preceding dental infection or trauma 3

Specific Infectious Syndromes

• Kawasaki disease presents with bilateral cervical lymphadenopathy, fever ≥5 days, "strawberry tongue," polymorphous rash, and swollen extremities—this is critical to identify due to risk of coronary artery aneurysm 4, 5
• Scarlet fever (Group A Streptococcus) causes "strawberry tongue" and cervical lymphadenopathy with characteristic rash, most common in ages 5-15 years 5

Malignant Etiologies (Must Be Excluded)

Lymphoma

• Burkitt lymphoma and diffuse large B-cell lymphoma commonly present with painless bilateral cervical lymphadenopathy in children 4
• Look for: firm, non-tender, fixed nodes >1.5 cm; B-symptoms (fever, night sweats, weight loss); rapid growth; extranodal involvement 4
• Head and neck tumors may cause jaw/gingival/maxillary swelling, difficulty swallowing, vision changes 4
• Oncologic emergencies possible: tumor lysis syndrome, airway compromise, superior vena cava syndrome 4

Jaw Tumors

• Ameloblastoma and juvenile ossifying fibroma are the most common pediatric jaw tumors 6
• Most present with mass/swelling (13/20 patients), though some are asymptomatic and found on imaging 6
• Malignant tumors (rhabdomyosarcoma, teratoma) are rare but possible 6

Non-Infectious, Non-Malignant Etiologies

Cherubism

• Bilateral jaw swelling in children ages 2-5 years, giving "cherubic" appearance 7
• Autosomal dominant fibro-osseous disorder, self-limiting 7
• Radiographs show bilateral multilocular radiolucent areas 7

Congenital Cysts

• Bronchogenic cysts, thyroglossal duct cysts can become infected and present with swelling 3
• Recurrent infections should prompt consideration of underlying cyst requiring surgical excision 3

Critical Diagnostic Approach

History Red Flags

• Duration >2 weeks without fluctuation = increased malignancy risk 4
• Fever, recent URI, dental problems, or trauma suggest infection 3
• B-symptoms (fever, night sweats, weight loss) suggest lymphoma 4
• Fever ≥5 days with rash and extremity swelling = Kawasaki disease 4, 5

Physical Examination Red Flags for Malignancy

• Fixed to adjacent tissues, firm consistency, size >1.5 cm, or ulceration of overlying skin 4
• Painless, non-tender nodes more concerning for malignancy 4
• Rapid growth, multiple node groups involved 4

Initial Imaging

• Ultrasound is first-line for pediatric neck masses—distinguishes solid vs. cystic, assesses vascularity, no radiation exposure 8, 2
• CT with contrast if deep involvement, airway compromise, or surgical planning needed 3
• Avoid CT in young children unless specific indication (abscess requiring drainage) due to radiation 8

Tissue Diagnosis

• Excisional or incisional biopsy preferred for suspected malignancy, with fresh tissue in saline 4
• Fine needle aspiration can be performed but may be inadequate in children 4
• Pus drainage/aspiration for culture if infection suspected—perform Gram stain and acid-fast stain immediately before antibiotics 3

Common Pitfalls to Avoid

• Do not assume bilateral = benign—lymphoma commonly presents bilaterally 4
• Do not give empiric antibiotics without evidence of bacterial infection (fever, warmth, erythema, tenderness)—this delays malignancy diagnosis and promotes resistance 4
• Do not miss Kawasaki disease—requires urgent treatment to prevent coronary complications 4, 5
• Do not rely on imaging alone to exclude malignancy—tissue diagnosis required for persistent masses 8
• Recurrent infections after treatment should prompt evaluation for underlying congenital cyst 3