What is the assessment and plan for a 5-year-old patient with a 1-month history of a 1.5-inch diameter enlarged lymph node, currently presenting with rhinorrhea, cough, and congestion?

Assessment and Plan for 5-Year-Old with 1-Month Enlarged Lymph Node

This 5-year-old with a 1.5-inch (approximately 3.8 cm) lymph node present for 1 month requires close observation with reassessment in 2 weeks, and if not completely resolved, proceed to excisional biopsy to rule out malignancy or nontuberculous mycobacterial (NTM) infection. 1, 2

Assessment

Current Clinical Picture

• Size and duration are concerning: A lymph node ≥1.5 cm that has persisted for ≥2 weeks without significant fluctuation places this child at increased risk for malignancy or chronic infection, even in the presence of current upper respiratory symptoms 1, 3
• Current URI symptoms may be misleading: While reactive cervical lymphadenopathy commonly occurs with respiratory infections in children and typically resolves with infectious symptoms or within a few days of completing treatment, the 1-month duration predates these current symptoms and suggests an alternative etiology 1, 2
• Age-specific consideration: Children aged 1-5 years are most susceptible to NTM lymphadenitis (particularly Mycobacterium avium complex), which accounts for approximately 80% of culture-proven NTM lymphadenitis cases in this age group 2, 4

Key Differential Diagnoses

• Nontuberculous mycobacterial lymphadenitis: Most likely given age, size (>1.5 cm), duration (1 month), and typical unilateral presentation 2, 4
• Reactive lymphadenopathy: Less likely given the prolonged duration beyond typical resolution timeframe 1
• Malignancy: Must be excluded given size >1.5 cm and duration >2 weeks 1, 3
• Kawasaki disease: Unlikely without other principal clinical features (conjunctivitis, rash, oral changes, extremity changes), though cervical lymphadenopathy ≥1.5 cm can be the initial presenting feature 1

Plan

Immediate Management

• Do NOT prescribe antibiotics empirically: In the absence of signs suggesting acute bacterial infection (such as rapid onset, fever, tenderness, overlying erythema), empiric antibiotic treatment should be avoided 1, 2
• Obtain tuberculosis testing: Perform PPD tuberculin skin test or interferon-gamma release assay (IGRA) immediately, as this is essential to differentiate tuberculous from nontuberculous mycobacterial infection 2, 4

Two-Week Reassessment

• Schedule follow-up in 2 weeks: The patient must be reassessed within 2 weeks to evaluate for resolution, progression, or persistence 1
• If lymph node has NOT completely resolved: Proceed to definitive workup as partial resolution may represent infection in an underlying malignancy 1
• If lymph node has completely resolved: Schedule one additional follow-up in 2-4 weeks to monitor for recurrence, which would prompt definitive workup 1

Definitive Workup if Persistent at 2 Weeks

• Excisional biopsy is the gold standard: This is the recommended treatment for children with suspected NTM cervical lymphadenitis, with a success rate of approximately 95% 2, 4
• Consider advanced imaging first: For larger lymph nodes (this node is approximately 3.8 cm) or those in difficult anatomical sites, obtain MRI or CT before surgery to assess extent and surgical planning 2
• Send tissue for: Histopathology, mycobacterial culture (both tuberculous and nontuberculous), and routine bacterial culture 2, 5

Special Considerations

• If PPD is strongly positive: Consider anti-tuberculosis therapy while awaiting lymph node culture results, particularly if the child has granulomatous disease on biopsy 2
• If surgical risk is high or recurrent disease: A clarithromycin-based multidrug regimen may be considered as an alternative to surgery for NTM lymphadenitis 2
• Monitor for Kawasaki disease: If fever persists beyond current URI symptoms and other principal clinical features develop (conjunctivitis, rash, oral changes, extremity changes), reassess for Kawasaki disease 1

Common Pitfalls to Avoid

• Do not mistake NTM lymphadenitis for bacterial infection: This commonly leads to inappropriate antibiotic treatment and delayed diagnosis 2
• Do not use corticosteroids: These can mask the histologic diagnosis of lymphoma or other malignancy and should be avoided without an appropriate diagnosis 3, 6
• Do not assume current URI explains the lymph node: The 1-month duration predates current symptoms and requires independent evaluation 1, 2