Synopsis
Differentiate involutional duct ectasia from active periductal infection, exclude malignancy in persistent retroareolar change, and manage abscess, fistula and smoking-related recurrence through a coordinated breast pathway.
- Duct ectasia describes dilated subareolar ducts containing secretions and commonly causes thick multiduct discharge, nipple retraction or a tender retroareolar lump.
- Periductal mastitis is inflammation around major ducts, is strongly associated with smoking and may progress to recurrent periareolar abscess or mammary duct fistula.
- Pain, erythema and fluctuation require ultrasound to identify a drainable collection; systemic illness requires urgent physiological assessment and same-day surgical input.
Investigation priorities
Demonstrate dilated ducts, inflammatory change and a drainable periareolar collection.
Management branches
A non-lactating adult who smokes has periareolar cellulitis and an ultrasound-confirmed abscess but is haemodynamically stable and suitable for outpatient care.
- Assess observations, sepsis, spreading cellulitis, skin necrosis, diabetes, immune status, penicillin allergy and previous MRSA; systemic illness, necrosis or other high-risk features require same-day admission and the separate intravenous pathway.
- Arrange ultrasound-guided aspiration or drainage and send pus for culture and susceptibility. An organised collection needs source control, not antibiotics alone.
Key medicines
FlucloxacillinNHS Highland adult local regimen: 500 mg by mouth four times daily for 7 to 10 days for breast abscess or 10 to 14 days for non-lactating mastitis. If systemically unwell and admitted, its separate local branch lists 1 to 2 g intravenously four times daily; breast infection is outside the selected 2 g IV product's listed indications, so use requires the local specialist/formulary pathway.Do not use with penicillin or other beta-lactam hypersensitivity or previous flucloxacillin-associated jaundice or hepatic dysfunction. Take the oral capsule on an empty stomach with a full glass of water and do not lie down immediately. For the selected IV product, dissolve 2 g in 40 mL water for injections for slow intravenous injection, or administer suitably diluted over 20 to 30 minutes. If creatinine clearance is below 10 mL/min, reduce the dose or extend the interval and do not exceed 1 g every 8 to 12 hours. Monitor potassium with high doses, especially with other hypokalaemia risks, and review renal/hepatic function, sodium load and neurotoxicity risk.
MetronidazoleNHS Highland adult local add-on for a smoker or recurrent abscess: 400 mg by mouth three times daily for the same 7 to 10 day abscess course or 10 to 14 day mastitis course. Its separate systemic-illness branch lists 500 mg intravenously three times daily; oral use is preferred when possible. Breast infection is outside Baxter's selected IV product indications, so this example depends on the local specialist/formulary pathway.Avoid in nitroimidazole hypersensitivity and take oral tablets during or after food. For the oral product, avoid alcohol during treatment and for at least 48 hours afterwards. If oral treatment exceeds 10 days, arrange regular clinical and laboratory review, especially leucocyte count, and monitor for peripheral or central neurological toxicity. For Baxter IV metronidazole, infuse 500 mg/100 mL over 20 to 60 minutes, change to oral as soon as feasible, avoid alcohol through 72 hours after treatment, and use prolonged IV therapy only after strict benefit-risk review with specialist clinical and biological surveillance. Advanced hepatic insufficiency requires dose reduction and serum-level monitoring; also check warfarin or other coumarins, lithium, renal-metabolite toxicity and neurological symptoms.