Breast Abscess Summary

Key Clinical Features

  • History of recent mastitis
  • Fever and/or general malaise
  • Painful, swollen lump in the breast
  • Redness, heat, and swelling of overlying skin

Management

  • Urgent referral to general surgeon
  • Ultrasound for confirmation
  • Drainage (needle aspiration or surgical)
  • Culture of fluid for antibiotic guidance
  • Antimicrobial therapy

Primary Pathogen

  • Staphylococcus aureus is most frequent

Risk Factors

  • Previous mastitis
  • Immunosuppression
  • S. aureus carriage
  • Poor socio-economic status
  • Poor hygiene

Breast Abscess: Diagnosis and Management

Medical guidelines for identifying and treating breast abscesses

Introduction

Breast infections (including infectious mastitis and breast abscess) more commonly affect women aged 15-45 years, especially those who are lactating. However, mastitis and breast abscess can occur at any age. Staphylococcus aureus is the most frequent pathogen isolated.

Lactational Abscess

Usually located in the peripheral region of the breast, more commonly in the upper and outer quadrant.

Non-Lactational Abscess

Tends to be located in the central/subareolar or lower quadrants of the breast.

Pathophysiology

A breast abscess is a localized collection of pus within the breast. It is a severe complication of mastitis, although it may occur without apparent preceding mastitis.

Predisposing Factors

Risk Factors

Several factors can increase the likelihood of developing a breast abscess. Identifying these risk factors can help in prevention and early intervention.

Previous mastitis
  • Delayed, inadequate, or inappropriate treatment of previous mastitis can lead to complications, including a breast abscess.
  • Sudden cessation of breastfeeding in women with lactational mastitis without effective milk removal is likely to progress to an abscess.
Immunosuppression - Women with diabetes mellitus or HIV infection, and those on immunosuppressive therapy, are at risk for developing recurrent breast infections.
Staphylococcus aureus carriage - Asymptomatic carriage of S. aureus on a person's skin or mucous membranes (colonization) is implicated in recurrent infections.
Poor socio-economic status - There is some evidence of a higher incidence of breast abscess (especially lactational) in low income women compared with higher income women.
Poor hygiene - Better maternal and infant hygiene reduces the risk of abscess formation.

Clinical Features

Suspicion of Breast Abscess

Suspect a breast abscess if the woman presents with one or more of the following signs and symptoms:

History

A history of recent mastitis that may not have resolved properly with treatment.

Systemic Symptoms

Fever and/or general malaise — these may have subsided if the woman has taken antibiotics for suspected infectious mastitis.

Local Symptoms

A painful, swollen lump in the breast, with redness, heat, and swelling of the overlying skin. On examination, the lump may be fluctuant with skin discoloration.

Management

Refer the woman urgently to a general surgeon for confirmation of diagnosis, drainage, and appropriate treatment.

Diagnostic Process

Ultrasound confirmation - Ultrasonography of an erythematous breast area may help diagnose an underlying abscess and can direct needle aspiration drainage. An abscess may appear as a well-circumscribed, macrolobulated, irregular, or ill-defined echo-poor compound cystic lesion with possible septae.
Drainage of the abscess - A breast abscess can be drained by ultrasound-guided needle aspiration or surgical drainage for therapeutic and diagnostic purposes. For complete drainage, multiple aspirations may be necessary (daily aspiration for 5-7 days).
Culture of fluid - Aspirated material from needle drainage should be sent for microbiology studies and cytology to look for underlying malignancy in addition to infection. This will guide the choice of antibiotic.
Antimicrobial therapy - Antimicrobial therapy is prescribed in addition to drainage of the abscess. Without drainage, antimicrobial therapy is unlikely to be successful because the abscess wall protects bacteria from antibiotics.

Treatment Considerations

Treatment Aspect Details Considerations
Antibiotic Therapy Based on culture results; initially empiric coverage for S. aureus Continue for 10-14 days; adjust based on culture results
Pain Management Analgesics as needed NSAIDs often effective for both pain and inflammation
Follow-up Regular monitoring until resolution Watch for recurrence or complications
Lactation Support Continue breastfeeding if possible Emptying the breast promotes healing; milk is safe for infant

Pathogen Information

Staphylococcus aureus is the most frequently isolated pathogen in breast abscesses. Understanding its characteristics is crucial for effective treatment.

Staphylococcus aureus

Gram-positive bacteria that commonly colonizes skin and nasal passages. Known for developing antibiotic resistance (MRSA strains).

Transmission

Often originates from the patient's own flora or from infant's mouth during breastfeeding. Can be transmitted through contaminated hands.

Antibiotic Sensitivity

Initial empiric therapy should cover both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) strains until culture results available.