Acute Bacterial Cervical Lymphadenitis

Acute bacterial cervical lymphadenitis is rapid onset, tender enlargement of one or more neck lymph nodes from bacterial infection, usually Staphylococcus aureus or group A streptococcus draining from the throat, scalp, teeth or skin. It is most common in children aged 1 to 5 years.

• Anaerobes (dental infection), Bartonella henselae (cat scratch disease), Mycobacterium tuberculosis and non tuberculous mycobacteria cause subacute or chronic forms.
• Risk factors: pharyngitis, tonsillitis, dental caries, scalp infection, impetigo, atopic dermatitis, HIV.

Unilateral, warm, tender, erythematous node (usually 2 to 6 cm) in the anterior triangle (jugulodigastric), with fever and malaise; may fluctuate as an abscess.

• Neck stiffness or torticollis if deep; trismus and drooling if parapharyngeal or retropharyngeal extension.
• Differential diagnosis: tuberculous lymphadenitis, non tuberculous mycobacterial infection, cat scratch disease, Kawasaki disease, infectious mononucleosis, toxoplasmosis, HIV, lymphoma, branchial cleft cyst, thyroglossal cyst, sialadenitis, mumps, metastatic cancer.
• Complications: abscess, airway compromise, parapharyngeal and retropharyngeal abscess, septic thrombophlebitis of the internal jugular vein (Lemierre syndrome), mediastinitis, bacteraemia, osteomyelitis, scarring.

Clinical, with imaging when abscess is suspected.

• Neck ultrasound to differentiate cellulitis from abscess; CT with contrast for deep neck infection.
• Full blood count, CRP, blood cultures if febrile; throat swab; needle aspiration for culture and Gram stain; Xpert MTB/RIF on aspirate if subacute.
• HIV test; tuberculin test or interferon gamma release assay if node persists over 2 weeks.

Antibiotics against staphylococci and streptococci, and drainage of any abscess.

• Supportive: analgesia, fluids, warm compresses, rest, dental review, observation of the airway.
• Pharmacological: flucloxacillin 500 mg four times daily for 7 to 10 days (children 12.5 to 25 mg/kg four times daily), or cefalexin 500 mg four times daily, or amoxicillin clavulanate 625 mg three times daily if dental or anaerobic source; penicillin allergy: clindamycin 300 to 450 mg three times daily (children 7 mg/kg three times daily). Severe or systemic: flucloxacillin 1 to 2 g IV every 6 hours (children 25 mg/kg every 6 hours) or ceftriaxone 2 g IV daily; MRSA risk: add vancomycin 15 to 20 mg/kg IV every 12 hours or give cotrimoxazole 960 mg twice daily. Cat scratch disease: azithromycin 500 mg then 250 mg daily for 4 days. Paracetamol 1 g (children 15 mg/kg) every 6 hours.
• Procedures: needle aspiration or incision and drainage of fluctuant node; drainage of deep neck abscess; extraction of infected tooth.
• Special groups: pregnancy, flucloxacillin or cefalexin; children, weight based dosing and exclusion of Kawasaki disease; HIV, evaluate for tuberculosis; elderly, exclude malignancy.
• Red flags: stridor, drooling, trismus, neck swelling spreading to chest, sepsis, node over 3 cm persisting beyond 2 weeks, hard fixed nodes.
• Follow-up: review at 48 to 72 hours; ultrasound if not improving at 5 days; biopsy if node persists beyond 4 to 6 weeks.