Lymphadenopathy

Background

• Lymphadenopathy is common and usually benign in the ED setting
• Normal lymph nodes are typically <1 cm; supraclavicular, popliteal, and iliac nodes >0.5 cm are considered abnormal
• Most ED presentations are reactive lymphadenopathy from regional infection
• Key EM concern is identifying malignancy or serious infection requiring urgent intervention

Clinical Features

• Location helps narrow differential:
  • Cervical — URI, pharyngitis, dental infection, mononucleosis, lymphoma, head/neck malignancy
  • Supraclavicular — high suspicion for malignancy (left: abdominal malignancy via Virchow node; right: mediastinal/lung pathology)
  • Axillary — upper extremity infection, cat scratch disease, breast cancer, lymphoma
  • Inguinal — STIs, lower extremity infection, lymphoma, pelvic malignancy
  • Generalized — viral (HIV, EBV, CMV), autoimmune (SLE), lymphoma, leukemia, medications
• Characteristics:
  • Tender, warm, mobile → reactive/infectious
  • Hard, fixed, nontender → concerning for malignancy
  • Matted nodes → granulomatous disease (TB, sarcoid) or lymphoma
  • Rapidly enlarging → infection or aggressive malignancy

Differential Diagnosis

Cervical Lymphadenopathy

• Hodgkin's lymphoma
• Non-Hodgkin's lymphoma
• Mononucleosis
• Toxoplasmosis
• Branchial cleft lesions
• Cat scratch disease
• Mycobacterial adenitis

Evaluation of Lymphadenopathy

Evaluation

• Most localized lymphadenopathy in young patients with obvious infectious source needs no workup
• Consider workup when:
  • Duration >4-6 weeks without improvement
  • Supraclavicular location
  • Node >2 cm without obvious infectious cause
  • Associated constitutional symptoms (weight loss, night sweats, fever)
  • Hard, fixed, or rapidly growing
• Labs (as indicated): CBC with differential, peripheral smear, ESR/CRP, LDH, uric acid, mono spot, HIV
• Imaging: CT with contrast if deep space infection or malignancy suspected; ultrasound to characterize superficial nodes
• Biopsy: Not typically performed in the ED; refer for excisional biopsy if malignancy suspected (avoid FNA alone for suspected lymphoma)

Management

• Treat the underlying cause
• If reactive from regional infection → treat the infection; lymphadenopathy should resolve over weeks
• If abscess suspected within node → I&D or aspiration
• If malignancy suspected → urgent outpatient referral for biopsy

Disposition

• Most patients with lymphadenopathy are discharged from the ED
• Admit if: associated sepsis, deep space infection requiring IV antibiotics, or airway compromise from cervical lymphadenopathy
• Urgent referral for: supraclavicular nodes, nodes >2 cm persistent >4 weeks, suspicion for malignancy

See Also

• Neck mass
• Infectious mononucleosis
• Lymphoma
• Cat scratch disease