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Other Names:
Mastitis, Breast Tissue Infection, Breast Abscess
Breast Infection

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Breast infection is inflammation of breast tissue caused by bacteria that enter the breast tissue through the cracks in the nipples. Breast infections usually occur in women who are breast-feeding.

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Breast infections are commonly caused by bacteria found on normal skin (Staphylococcus aureus). The bacteria enter through a crack in the skin of the nipple.

The infection takes place in the fatty tissue and causes swelling of the tissue around the milk ducts. This swelling in the tissue surrounding the milk ducts compresses them resulting in pain and swelling of the infected breast.

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  • Breast pain
  • Lump in breast
  • Breast enlargement which may be on one side only
  • Signs of inflammation like swelling, tenderness, redness and heat in breast tissue
  • Nipple discharge which may contain pus or blood
  • Changes in nipple sensation
  • Itching around the nipple
  • Tender and/or enlarged lymph nodes in armpit on the same side
  • Fever

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In severe infections, an abscess (localized accumulation of pus) may develop in the breast. Abscesses require more extensive treatment, including incision and drainage followed by antibiotics. Discontinuation of breast-feeding and suppression of milk production may be necessary to prevent engorgement of breasts.

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What You Can Do

  • Apply moist heat to the infected breast tissue for 15 to 20 minutes four times a day.
  • Antibiotics are usually very effective in treating mastitis.
  • If you are breast feeding, continue to breast-feed or pump out the breast milk to alleviate engorgement while receiving treatment.
  • Good care of the breasts, especially after delivery and while breast-feeding, may decrease the risk to develop breast infections.

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Breast Infection