Mastitis

1. Epidemiology
   1. Incidence: 9-33% of lactating women
   2. Most common in first few weeks and nearly all cases within first 3 months
2. Pathophysiology
   1. Generally occurs in Lactation several weeks postpartum
   2. Bacteria enter through a cracked nipple
3. Etiology
   1. Staphylococcus aureus
   2. Escherichia coli
   3. HaemophilusInfluenzae
4. Symptoms
   1. Fatigue
   2. Malaise
   3. Myalgias
   4. Headache
5. Signs
   1. Fever
   2. Unilateral Breast inflammation
      1. Warmth
      2. Tenderness
      3. Erythema
   3. Observe for signs of Breast abscess
      1. Requires needle aspiration
6. Labs: Milk Culture
   1. Indications (not routine)
      1. Severe Mastitis
      2. Refractory despite optimal antibiotics for at least 48 hours
      3. Hospital acquired infection
   2. Technique
      1. Cleanse nipple
      2. Hand express small quantity of Breast milk and discard
      3. Hand express a sample into a sterile container
7. Differential Diagnosis
   1. Inflammatory Breast Cancer
8. Management: General Measures
   1. Continue with frequent Breastfeeding
      1. Risk of Breast abscess if Breast engorgement occurs
      2. Safe for infant to continue to feed despite infection (except if mother HIV positive)
      3. Ensure proper technique (see prevention below)
   2. Tylenol
   3. Ensure adequate hydration
   4. Apply warm packs and local massage
   5. Alternate feeding positions
   6. Antifungals (Monilial Infection)
      1. Topical Antifungals on Breast
      2. Oral Nystatin for infant
9. Management: Antibiotics
   1. Course: 10 to 14 days
   2. Coverage: Staphylococcus aureus (or as directed by culture)
   3. Antibiotics: Nursing Mothers
      1. Amoxacillin-Clavulanate (Augmentin) 875 mg orally twice daily
      2. Cephalexin (Keflex) 500 mg orally four times daily
      3. Dicloxacillin 500 mg orally four times daily
      4. Clindamycin 300 mg orally four times daily (for MRSA)
      5. Ciprofloxacin 500 mg orally twice daily (for MRSA)
   4. Antibiotics: Non-Breast Feeding women
      1. Trimethoprim-sulfamethoxazole (Septra) 160mg/800 mg orally twice daily (for MRSA)
10. Complications
    1. Breast abscess
       1. Obtain bacterial culture
       2. Treat with needle aspiration or Incision and Drainage
11. Follow-up
    1. If not better in 48 hours examine Breast for abscess
       1. Consider Incision and Drainage
    2. Early antibiotics prevent abscess formation
12. Prevention
    1. Optimal Breast Feeding Technique with good latch-on by infant
    2. Address predisposing factors early
       1. Sore nipples suggest problems
          1. Correct latch-on problems
          2. Address dry nipples with lanolin
          3. Avoid plastic-backed Breast pads
          4. Evaluate infant for anatomic problems (e.g. short frenulum, Cleft Palate)
       2. Cracked nipples colonized with Staphylococcus aureus should be treated
          1. Oral antibiotics (e.g. Dicloxacillin) are preferred
          2. Livingstone (1999) J Hum Lact 15:241-6
       3. Blocked milk ducts should be unblocked
          1. Blocked ducts will appear with a bleb overlying a tender, red area adjacent to nipple
          2. Remove bleb with moist cloth
       4. Yeast infection should be treated (both infant and mother)
          1. Infant: See Thrush for management options
          2. Mother
             1. Topical agents: Nystatin or Ketoconazole
             2. Oral agents: Fluconazole 400 mg on day #1, then 200 mg orally daily for 10 days
             3. Chetwynd (2002) J Hum Lact 18:168-71
13. References
    1. Spencer (2008) Am Fam Physician 78(6): 727-32
    2. Barbosa-Cesnik (2003) JAMA 289:1609-12