What is the workup for mastitis?

Workup for Mastitis

The diagnostic workup for mastitis should be primarily clinical, based on symptoms such as fever, malaise, focal breast tenderness, and overlying skin erythema, without routine need for laboratory tests or imaging in most cases. 1

Clinical Assessment

• Key symptoms to evaluate:

  • Fever
  • Malaise
  • Focal breast tenderness
  • Overlying skin erythema or hyperpigmentation
  • Breast pain
  • Breast swelling

• Risk factors to identify:

  • Lactation (most common in first 3 months postpartum)
  • Improper breastfeeding technique
  • Milk stasis
  • Cracked nipples
  • Overstimulation of milk production
  • Tissue trauma from aggressive breast massage

Diagnostic Testing

• Initial workup:

  • Clinical diagnosis is sufficient for uncomplicated cases 1
  • Laboratory tests are not routinely needed for initial diagnosis

• When to obtain milk cultures:

  • Severe or unusual presentation
  • No response to initial antibiotic therapy
  • Hospital-acquired infections
  • Recurrent mastitis
  • Immunocompromised patients 1

• Imaging indications:

  • Ultrasound: Indicated when abscess is suspected, particularly in:
    • Immunocompromised patients
    • Worsening symptoms despite treatment
    • Recurrent symptoms
    • No improvement after 48-72 hours of antibiotics 1
  • Mammography: Not typically needed for acute mastitis but may be considered for:
    • Non-lactational mastitis in women over 40 years
    • Inflammatory breast cancer suspicion 2
    • Persistent symptoms despite appropriate treatment

• Biopsy considerations:

  • Indicated when malignancy is suspected
  • Core needle biopsy is preferred over fine needle aspiration 2
  • Should be considered for:
    • Non-lactational mastitis
    • Persistent or recurrent symptoms despite appropriate treatment
    • Atypical presentation

Differential Diagnosis

• Inflammatory breast cancer
• Breast abscess
• Granulomatous mastitis
• Ductal ectasia
• Infected sebaceous cyst
• Dermatitis

Management Algorithm

1. Initial approach (1-2 days):

   • Conservative measures:
     • NSAIDs for pain and inflammation
     • Ice application
     • Continue breastfeeding from affected breast
     • Minimize excessive pumping 1

2. If no improvement after 1-2 days:

   • Initiate antibiotics targeting common skin flora (Staphylococcus, Streptococcus)
   • Continue supportive measures

3. If worsening or no improvement after antibiotics:

   • Obtain ultrasound to evaluate for abscess
   • Consider milk culture to guide antibiotic therapy
   • Evaluate for complications

4. For severe cases or signs of sepsis:

   • Hospitalization
   • Intravenous antibiotics
   • Surgical consultation if abscess is present 1

Common Pitfalls to Avoid

• Overtreatment pitfalls:

  • Immediate antibiotics without trial of conservative measures
  • Recommending cessation of breastfeeding
  • Excessive breast massage (can worsen condition)
  • Excessive pumping (can worsen condition)
  • Heat application (may worsen inflammation) 1

• Diagnostic pitfalls:

  • Failing to consider inflammatory breast cancer in non-lactational cases
  • Missing an underlying abscess
  • Not obtaining cultures in recurrent or non-responsive cases
  • Overlooking granulomatous mastitis, which requires specific treatment 3

Remember that most cases of mastitis are due to inflammation rather than true infection, and conservative measures are often sufficient for initial management. Proper breastfeeding technique is crucial for both treatment and prevention of recurrence 1, 4.