Breast Infection Causes

Breast Infection Causes

Mastitis (inflammation of breast tissue) is a common benign cause of a breast mass. It is commonly seen in women after childbirth while breastfeeding. These masses are often quite painful. Women who are not breastfeeding can also develop mastitis. In healthy women, mastitis is rare. However, women with diabetes, chronic illness, AIDS, or an impaired immune system may be more susceptible to the development of mastitis.

Bacteria normally found in a baby's mouth or on the nipple can enter the milk ducts through small cracks in the skin of the nipple and can multiply rapidly in the breast milk. This can lead to a superficial small area of inflammation (frequently from streptococcal bacteria) or a deeper walled-off infection or abscess (frequently from staphylococcal bacteria). 

Mild temperature elevations (previously termed milk fever) accompanied by some breast or nipple soreness is usually secondary to engorgement and dehydration immediately (24-72 hours) after delivery and is treated by improved breastfeeding technique. The body temperature should not be above 39°C (102.2°F), nor should the fever persist for longer than about 4-16 hours. This condition may also occur in women who are not breastfeeding and have not completely suppressed lactation yet.

About one to three percent of breastfeeding mothers develop mastitis, usually within the first few weeks after delivery. Most breast infections occur within the first or second month after delivery or at the time of weaning. Typically, the infection is only in one breast. Engorgement and incomplete breast emptying can contribute to the problem and make the symptoms worse.

Chronic mastitis occurs in women who are not breastfeeding. In postmenopausal women, breast infections may be associated with chronic inflammation of the ducts below the nipple. Hormonal changes in the body can cause the milk ducts to become clogged with dead skin cells and debris. These clogged ducts make the breast more prone to bacterial infection. This type of infection tends to come back after treatment with antibiotics.