What is the appropriate evaluation and treatment for a swollen lymph node?

Evaluation and Management of Swollen Lymph Nodes

The appropriate evaluation of a swollen lymph node requires a systematic approach including thorough history, physical examination, targeted laboratory testing, imaging, and biopsy when indicated, with excisional biopsy being the gold standard for persistent lymphadenopathy to rule out malignancy.

Initial Assessment

History and Physical Examination

• Assess for:
  • Duration of lymphadenopathy (acute vs persistent)
  • Associated symptoms, particularly B symptoms (fever, night sweats, weight loss >10% over 6 months)
  • Recent infections or exposures
  • Medication use
  • Family history of autoimmune disease or malignancy
  • Travel history 1

Physical Examination of Lymph Nodes

• Document:
  • Size (nodes >1 cm are considered enlarged)
  • Location and distribution (localized vs generalized)
  • Consistency (soft, firm, hard)
  • Mobility (mobile vs fixed)
  • Tenderness
  • Overlying skin changes 1

Diagnostic Algorithm

Step 1: Laboratory Testing

• Complete blood count with differential
• Targeted testing based on clinical suspicion:
  • HIV testing
  • Hepatitis B and C serology
  • EBV, CMV serology if infectious mononucleosis suspected 1

Step 2: Imaging

• Ultrasound: First-line imaging modality

  • Characterizes node size, internal architecture, and vascularity
  • Guides FNA if needed 1, 2

• CT or MRI with contrast: Indicated when:

  • Node ≥5 cm in diameter
  • Suspicion of deep extension
  • Malignancy suspected
  • Ultrasound findings inconclusive 1

• PET/CT: Recommended for staging if malignancy is confirmed or lymphoma suspected 1, 3

Step 3: Tissue Sampling

• Fine-needle aspiration (FNA):

  • Indicated for persistent lymphadenopathy (>3-4 weeks)
  • Nodes with suspicious features (hard, fixed, >1 cm)
  • Supraclavicular location (high risk for malignancy)
  • Abnormal imaging findings 1

• Excisional biopsy (gold standard for lymphoma diagnosis):

  • Indicated when lymphadenopathy persists >4 weeks despite antibiotics
  • Suspicious features for malignancy
  • FNA is non-diagnostic 1, 3

Management Based on Presentation

Acute Lymphadenopathy (<4 weeks)

• If signs of infection present:
  • Single course of broad-spectrum antibiotics
  • Reassessment within 2 weeks of antibiotic treatment 1

Persistent Lymphadenopathy (>4 weeks)

• Excisional biopsy to rule out malignancy
• Histological analysis essential, especially for lymphoma workup 4, 5

Management After Diagnosis

• Treatment directed at underlying cause:
  • Infectious: Appropriate antimicrobial therapy
  • Malignant: Referral to oncology for staging and treatment
  • Autoimmune: Immunomodulatory therapy 1

Indications for Specialist Referral

• Multiple enlarged nodes in different regions
• Persistent lymphadenopathy >4 weeks despite antibiotics
• Presence of B symptoms
• Abnormal complete blood count
• Suspicion of lymphoma or leukemia 1

Special Considerations

Supraclavicular Lymphadenopathy

• Highest risk for malignancy (90% in adults)
• Always warrants prompt investigation 1

Post-COVID-19 Vaccination

• Axillary lymphadenopathy may persist for weeks
• Consider timing of vaccination before ordering extensive workup 1

Common Pitfalls to Avoid

• Delaying biopsy in patients with persistent lymphadenopathy >4 weeks
• Overlooking supraclavicular lymphadenopathy
• Relying solely on FNA when lymphoma is suspected
• Using corticosteroids before establishing a diagnosis 1

Follow-up

• For benign reactive lymphadenopathy: Reassessment in 2-4 weeks
• For malignant causes: Follow-up per oncology protocols
• For partially resolved infectious lymphadenopathy: Complete course of antibiotics and reassess 1

In cases of suspected malignancy, particularly lymphoma, excisional biopsy with histopathological examination remains the definitive diagnostic approach, as it provides adequate tissue for comprehensive analysis and accurate diagnosis 3, 5.