What is the treatment for a postpartum woman with puerperal mastitis?

Treatment of Puerperal Mastitis

For postpartum women with puerperal mastitis, continue breastfeeding or milk expression while initiating antibiotic therapy with dicloxacillin 500 mg orally four times daily or cephalexin 500 mg orally four times daily, targeting Staphylococcus aureus as the primary pathogen. 1, 2, 3

Immediate Management Priorities

Continue Breastfeeding

• Regular feeding or milk expression from the affected breast is essential and must not be discontinued, as stopping worsens the condition and increases abscess risk 1, 2, 4
• Breastfeeding does not pose risk to the infant and actively helps resolve the mastitis 3, 4
• Even if an abscess develops, breastfeeding can continue on the affected side provided the infant's mouth does not contact purulent drainage 1, 2

First-Line Antibiotic Selection

For methicillin-susceptible S. aureus (the majority of cases):

• Dicloxacillin 500 mg orally four times daily is the preferred oral agent 2, 3, 4
• Cephalexin 500 mg orally four times daily is an equally effective alternative, particularly for penicillin-allergic patients 2, 3, 4
• Both antibiotics are safe during breastfeeding with minimal milk transfer and no adverse infant effects 2, 3

For penicillin-allergic patients:

• Clindamycin is an acceptable alternative, though use with caution as it may increase gastrointestinal side effects in the infant 2, 3
• Azithromycin or erythromycin are alternatives, but avoid macrolides during the first 13 days of infant life due to very low risk of infantile hypertrophic pyloric stenosis 2, 3

Critical Consideration: MRSA Coverage

The emergence of methicillin-resistant S. aureus (MRSA) has fundamentally changed mastitis management over the past decade. 5, 6

Consider MRSA coverage if:

• High local MRSA prevalence exists 3
• Previous MRSA infection documented 3
• No response to first-line therapy within 48-72 hours 3, 6
• Patient is a healthcare worker 6

For suspected or confirmed MRSA:

• Clindamycin is the preferred oral agent 2, 3
• Studies show 64.2% of S. aureus isolates in hospitalized mastitis patients were oxacillin-resistant 5

Supportive Care

• Pain management with appropriate analgesics is essential, as pain can exacerbate symptoms 1
• Optimize breastfeeding technique, often with lactation consultant assistance 4
• Frequent, complete breast emptying reduces mastitis risk 4

Indications for Hospitalization

Hospitalize if:

• Fever and chills persist despite outpatient antibiotics, indicating systemic involvement 1, 2
• Concern for sepsis develops 1
• Oral antibiotic therapy fails 2

During hospitalization:

• Provide intravenous antibiotics if oral therapy inadequate 2
• Ensure access to breast pump if prolonged separation from infant occurs 1, 2
• Provide trained breastfeeding support staff 1, 2
• Schedule procedures to allow breastfeeding or milk expression 1

Management of Complications

Breast Abscess (occurs in ~10% of cases)

If abscess develops: 1, 3, 4

• Perform ultrasound-guided needle aspiration as the preferred drainage method 2
• Surgical incision and drainage if needle aspiration inadequate 4, 5
• Continue antibiotics targeting causative organism 4
• Breastfeeding can continue on affected side if infant's mouth does not contact purulent drainage 1, 2, 4

Note: Patients requiring incision and drainage are more likely to have oxacillin-resistant S. aureus, longer symptom duration, and longer hospitalization 5

Monitoring and Follow-Up

• Reevaluate within 48-72 hours if symptoms worsen or fail to improve to rule out abscess formation 3
• Consider alternative antibiotics based on culture results if obtained 3
• Early treatment prevents abscess formation, which can be avoided by prompt antibiotic therapy and continued breastfeeding 4

Critical Pitfalls to Avoid

• Never discontinue breastfeeding, as this worsens mastitis and dramatically increases abscess risk 2, 4, 5
• Avoid overstimulation, excessive pumping, heat application, and aggressive massage, which exacerbate inflammation 2
• Do not delay antibiotic treatment when indicated, as this increases abscess formation risk (occurs in approximately 10% of cases) 3, 4
• Avoid doxycycline, metronidazole, and TMP-SMX in breastfeeding women due to potential infant risks 2