How to diagnose a breast abscess in a breastfeeding patient?

Diagnosing Breast Abscess in Breastfeeding Patients

A breast abscess in a breastfeeding woman should be diagnosed using ultrasound imaging to confirm the presence and extent of the abscess collection, along with evaluation of clinical symptoms including focal breast tenderness, overlying skin erythema, and systemic symptoms. 1

Clinical Presentation

The key clinical findings that suggest a breast abscess include:

• Focal breast tenderness
• Overlying skin erythema or hyperpigmentation
• Systemic symptoms (fever, malaise)
• Palpable breast mass or area of induration
• Worsening symptoms despite antibiotic treatment for mastitis

Most breast abscesses develop during the first 100 days postpartum, with approximately 68.8% occurring within the first 60 days after delivery 2.

Diagnostic Algorithm

1. Physical Examination:

   • Look for focal breast tenderness
   • Check for overlying skin erythema or hyperpigmentation
   • Assess for a palpable mass or area of induration
   • Evaluate for systemic symptoms (fever, chills)

2. Ultrasound Imaging:

   • Ultrasound is the imaging modality of choice due to no radiation exposure 1
   • Confirms the presence of an abscess collection
   • Determines the size and extent of the abscess
   • Differentiates between mastitis (inflammatory changes without fluid collection) and abscess (defined fluid collection)
   • Guides potential aspiration or drainage procedures

3. Microbiological Testing:

   • Obtain samples of milk or abscess material for microbiological testing 2
   • Identify causative organisms, particularly Staphylococcus aureus
   • Determine antibiotic sensitivity, especially methicillin resistance

Key Diagnostic Features on Ultrasound

• Well-defined hypoechoic or anechoic collection
• Internal echoes or debris
• Peripheral vascularity on color Doppler
• Surrounding inflammatory changes

Important Considerations

• Breast abscesses occur in approximately 10% of mastitis cases 1
• Early diagnosis is critical to prevent complications and preserve breastfeeding
• Continued breastfeeding is an essential component of treatment and does not pose risk to the infant 1
• Ultrasound-guided needle aspiration is preferred over surgical drainage when possible 2, 3

Differential Diagnosis

Be aware of rare but important conditions that can mimic breast abscess:

• Inflammatory breast cancer (consider in cases with persistent symptoms despite appropriate treatment) 4
• Squamous cell carcinoma of the breast (rare but can present as breast abscess, especially in post-menopausal women) 4

Management Approach Based on Diagnosis

Once diagnosed, management should include:

• Antibiotics effective against Staphylococcus aureus (dicloxacillin or cephalexin) for 10-14 days 1
• Ultrasound-guided needle aspiration for abscesses smaller than 3 cm 5
• Ultrasound-guided catheter drainage for abscesses 3 cm or larger 5
• Continued breastfeeding to facilitate milk removal 1, 6
• Pain management with pregnancy-safe analgesics (acetaminophen, ibuprofen) 1

Pitfalls to Avoid

• Discontinuing breastfeeding can worsen engorgement and slow recovery 1
• Failure to obtain microbiological samples may lead to ineffective antibiotic therapy
• Surgical drainage without ultrasound guidance may result in unnecessary scarring and disruption of milk ducts 2
• Missing an underlying malignancy in cases with atypical presentation or poor response to treatment 4

Maintaining breastfeeding during treatment of breast abscess does not negatively affect treatment outcomes when the abscess is treated appropriately 6, and should be encouraged to support both maternal recovery and infant health.