Lump with Pus on the Neck: Causes, Diagnosis, and When to Seek Urgent Care

Possible Causes of a Pus-Filled Neck Lump

• Boil (furuncle): Staphylococcus infection of a hair follicle or oil gland.
• Abscess: Localized pus collection from bacterial infection, foreign body, or injury.
• Cystic acne: Severe inflammatory acne forming deep, pus-filled nodules.
• Cellulitis: Spreading skin infection with redness, warmth, swelling, and often fever.
• Sebaceous cyst: Blocked oil gland filled with keratin; can become infected.
• Hidradenitis suppurativa: Chronic inflammatory condition affecting apocrine sweat glands, often in neck/axilla/groin.
• Infected lymph node: Bacterial or viral infection causing tender, swollen nodes.
• Tuberculosis (scrofula): Rare; causes matted, suppurative cervical lymph nodes.

Medical Evaluation

See a doctor for proper diagnosis. Expect a physical exam, medical history review, and possibly blood tests, ultrasound, or CT imaging. Treatment depends on the cause:

• Antibiotics (oral or IV) for bacterial infections.
• Incision and drainage for fluctuant abscesses.
• Surgical excision for recurrent cysts or hidradenitis.

Red Flags: Seek Immediate Care

• Rapidly spreading redness or swelling.
• High fever (>101°F / 38.3°C).
• Red streaks radiating from the lump (lymphangitis).
• Difficulty swallowing, breathing, or neck movement.