Subareolar Abscess

Subareolar abscess is a collection of pus beneath the nipple and areola, arising from infected and blocked subareolar ducts. It occurs mainly in non lactating women aged 20 to 50 years, with smoking as the main cause, and it often recurs. It matters because it causes severe pain, forms a fistula between the duct and areolar skin, and often needs surgery.

• Risk factors: smoking, periductal mastitis, nipple inversion or piercing, diabetes, obesity, previous breast infection.
• The infection is usually mixed with anaerobes and Staphylococcus aureus.
• Surgery after the abscess has settled reduces recurrence.

Women have a tender, hot, fluctuant lump at or beside the areola, with redness, nipple retraction, nipple discharge and fever. A chronic fistula discharges pus at the areola margin.

• Mass directly beneath or beside the areola, fluctuant when mature.
• Sinus or fistula at the areolar edge in chronic cases.
• Differential diagnosis: periductal mastitis, lactational abscess, infected sebaceous cyst, granulomatous mastitis, tuberculous abscess, hidradenitis suppurativa, breast cancer, intraductal papilloma, Montgomery gland abscess.
• Complications: recurrent abscess, mammary duct fistula, nipple deformity, sepsis, scarring, delay in diagnosis of cancer.

The approach is examination and ultrasound with culture of the pus.

• Examination of the breast, nipple and axilla; temperature.
• Ultrasound to confirm a fluid collection and measure it, and to show a track to the nipple; mammography if age is 40 years or above.
• Pus culture (aerobic and anaerobic); full blood count, C-reactive protein, glucose.
• Core biopsy if a mass persists after the abscess has settled.

The principle is drainage with antibiotics, followed by removal of the diseased duct to prevent recurrence.

• Supportive: stop smoking; warm compress; paracetamol; supportive bra; dressing of the wound; control diabetes; remove nipple piercing.
• Pharmacological: lignocaine 1 percent infiltration, 5 to 15 mL (maximum 3 mg/kg, not above 200 mg); amoxicillin-clavulanate 625 mg oral 8-hourly for 7 to 10 days after drainage; severe infection: ceftriaxone 2 g IV once daily plus metronidazole 500 mg IV 8-hourly until afebrile for 24 hours, then oral amoxicillin-clavulanate to complete 10 to 14 days; penicillin allergy: clindamycin 300 mg oral 6-hourly plus ciprofloxacin 500 mg oral 12-hourly; paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours); ibuprofen 400 mg oral 8-hourly with food for 3 to 5 days.
• Procedures: ultrasound guided needle aspiration, repeated every 1 to 3 days (first choice for abscess less than 5 cm); incision and drainage for large or failed aspiration, with a small incision at the areola edge and a wick; definitive total duct excision with fistulectomy after 4 to 6 weeks, once infection has resolved, for recurrence or a fistula; biopsy of the cavity wall if it does not heal.
• Special groups: women with diabetes need insulin and a full 14 day course; smokers are counselled that recurrence after surgery is higher if smoking continues.
• Red flags: fever above 38.5 degrees Celsius persisting beyond 48 hours, spreading cellulitis, tissue necrosis, a mass persisting after healing, bloody discharge, hard fixed mass.
• Follow-up: wound review every 2 to 3 days; review at 1 week and 4 weeks with ultrasound; surgical review for duct excision at 4 to 6 weeks; breast examination at 3 months.