What is the recommended management for an adult with mastitis?

Treatment for Adult Mastitis

For lactational mastitis, initiate treatment with effective milk removal and supportive care; add antibiotics (dicloxacillin or cloxacillin as first-line) only if symptoms persist beyond 12-24 hours or if systemic symptoms are severe, and use ultrasound-guided aspiration rather than surgical drainage for abscesses 1, 2.

Distinguishing Infectious from Non-Infectious Mastitis

The critical first step is determining whether mastitis is infectious or inflammatory:

• Infectious lactational mastitis presents with thick fluid collections, systemic symptoms (fever, malaise), and localized breast findings (erythema, warmth, tenderness)
• Non-infectious inflammatory mastitis presents with breast inflammation but without purulent collections or severe systemic symptoms

This distinction matters because infectious mastitis requires intervention while non-infectious cases need only supportive care 1.

Lactational Mastitis Management Algorithm

Initial Management (First 12-24 hours)

• Effective milk removal is the most essential treatment component and may make antibiotics unnecessary 3
• Continue breastfeeding from the affected breast during treatment 3
• Apply supportive measures: adequate rest, hydration, and analgesics
• Ensure proper latch and feeding technique to prevent milk stasis

When to Add Antibiotics

Add antibiotics if:

• Symptoms persist beyond 12-24 hours despite effective milk removal
• Severe systemic symptoms present at onset (high fever, rigors)
• Presence of a phlegmon (requires minimum 10 days of antibiotics) 1

First-line antibiotic: Dicloxacillin or cloxacillin, as most bacterial mastitis is caused by Staphylococcus aureus resistant to beta-lactamase sensitive antibiotics 3. These agents have minimal transfer to breast milk 3.

Alternative: If beta-lactam allergy exists, obtain milk culture to guide therapy 3.

Managing Fluid Collections/Abscesses

For abscesses <5 cm:

• Ultrasound-guided needle aspiration is recommended 4
• Combine with appropriate antibiotics 4

For thick fluid collections not amenable to aspiration:

• Stab incision with drain placement (without packing) 1
• Office procedure is preferred; operative drainage only if patient cannot tolerate office procedure 1

For abscesses >5 cm:

• No clear evidence favoring initial surgery versus aspiration/drainage 4
• Clinical judgment based on patient tolerance and collection characteristics

Critical pitfall: Avoid incision and drainage as first-line intervention. The evidence strongly supports aspiration-based approaches, which reduced incision and drainage rates from 8% to 0.7% with sustained improvement 2.

Non-Lactational Mastitis

Periductal Mastitis with Squamous Metaplasia (PDM-SMOLD)

• Presents with recurrent abscesses, distinct from other periductal mastitis
• Initial treatment: Antibiotics plus aspiration for fluid collections 1
• Surgical excision indicated for: Fistula formation or recurrent episodes
• Use radial incision to remove diseased ducts within and below the nipple 1

Periareolar Abscess (Most Common Non-Puerperal Form)

• For abscesses <5 cm: Needle aspiration/drainage with antibiotic therapy 4
• For abscesses >5 cm: No definitive recommendation between surgery or aspiration; clinical judgment required 4

Granulomatous Mastitis

Diagnosis Requirements

• Mandatory: Pathology confirmation via core biopsy showing characteristic granulomatous findings 1
• Distinguish between cystic neutrophilic granulomatous mastitis (CNGM) and idiopathic granulomatous mastitis (IGM)

Cystic Neutrophilic Granulomatous Mastitis (CNGM)

• Associated with Corynebacterium infection
• Treatment: Empiric doxycycline 1

Idiopathic Granulomatous Mastitis (IGM)

No role for empiric antibiotics unless specific bacterium identified 1

Treatment algorithm for worsening symptoms:

1. First-line: Repeated intralesional steroid injections 1, 5
2. Avoid: Surgical excision or repeated aspirations 1
3. Refractory cases: Oral steroids 1
4. Persistent refractory cases: Advanced biologic agents (methotrexate or azathioprine) 1

Important counseling points:

• Cases often recur and can take up to 18 months to resolve 1
• Steroid-based combination therapy shows the most consistent favorable signal for recurrence reduction 5

Imaging Recommendations

• Ultrasound is the primary imaging modality for all mastitis presentations 2, 6
• Ultrasound assessment increased from 38% to 77% with standardized pathways and should be routine 2
• Use ultrasound to identify fluid collections amenable to aspiration
• Mammography and MRI reserved for cases mimicking malignancy or defining disease extent 6

Key Practice Points

Antibiotic compliance: Standardized pathways improved antibiotic guideline compliance from 34% to 58%, emphasizing the importance of protocol-driven care 2.

Specialist follow-up: Essential for all mastitis cases, with rates improving from 43% to 96% with standardized approaches 2. This ensures proper resolution monitoring and prevents complications.

Breastfeeding continuation: Proper treatment and patient education are crucial to prevent premature cessation of breastfeeding 7. Women can and should continue breastfeeding from the affected breast during treatment 3.

Common pitfall: Avoid routine surgical drainage. The shift from incision and drainage to aspiration-based approaches represents a major quality improvement in mastitis management 2.