A breast infection (mastitis) is rare, except around the time of childbirth (see Postdelivery Period: Breast Infection) or after an injury or surgery. The most common symptom is a swollen, red area that feels warm and tender. An uncommon type of breast cancer called inflammatory breast cancer (see Breast Disorders: Types) can cause similar symptoms. A breast infection is treated with antibiotics.
A breast abscess, which is even rarer, is a collection of pus in the breast. An abscess may develop if a breast infection is not treated. An abscess is usually drained surgically and may be treated with antibiotics.
Last full review/revision November 2008 by Victor G. Vogel, MD, MHS