Swollen Lymph Nodes in Neck/Throat: Causes, Red Flags & When to See a Doctor

Cervical Lymphadenopathy: Etiologies and Assessment

Lymph nodes >1 cm in neck are abnormal. Location, consistency, mobility, and associated symptoms guide diagnosis.

Common Causes

Infectious (most common)

• Viral: URI, EBV (mono), CMV, HIV, HSV.
• Bacterial: Strep throat, TB, cat-scratch, syphilis.
• Fungal/Parasitic: Histoplasmosis, toxoplasmosis.

Inflammatory/Autoimmune

• SLE, RA, Sjögren's, sarcoidosis, Kawasaki, Kikuchi-Fujimoto.

Malignancy

• Lymphoma (Hodgkin/Non-Hodgkin), leukemia.
• Metastatic: SCC (oral, laryngeal, thyroid), melanoma.

Other

• Drug reactions (phenytoin, allopurinol), serum sickness.
• Post-vaccination (COVID, influenza).
• Benign reactive hyperplasia.

Red Flags for Malignancy

• Size >2 cm, firm/hard, fixed/matted, non-tender.
• Supraclavicular location (Virchow's node = GI malignancy).
• Persistent >2-4 weeks despite antibiotics.
• Systemic: weight loss, night sweats, fever, fatigue.

Diagnostic Approach

1. History: duration, travel, exposures, medications, B symptoms.
2. Exam: all node groups, liver/spleen, skin, oropharynx.
3. Labs: CBC, ESR/CRP, LFTs, LDH, HIV, EBV/CMV serology, PPD.
4. Imaging: US (nodes), CT neck/chest/abdomen if malignancy suspected.
5. Biopsy: Excisional preferred (architecture); FNA if lymphoma low suspicion.

When to Refer

• Red flags present, persistent >2-4 weeks, diagnostic uncertainty.
• ENT, hematology/oncology, infectious disease as indicated.