The evaluation of a breast abscess begins with a medical history and physical examination.

Physical findings in a person with a breast abscess may include:

• Localized breast swelling
• Localized breast tenderness
• Localized skin redness
• Cloudy discharge from breast
• Nipple and skin retraction may be present in the infected breast.
• One or more lymph nodes in the armpits may be swollen.

The diagnosis of a breast abscess can be made without testing.

Tests that may be used to evaluate a breast abscess include:

• Wound culture
• To identify the infecting bacteria
• Complete blood count
• Erythrocyte sedimentation rate

Less common tests used to evaluate breast abscesses include:

• Mammography
• Breast biopsy