Exams and Tests

Your doctor can usually diagnose mastitis based on your symptoms and an examination of the affected breast. Tests are usually not needed. But they may be done to confirm a diagnosis or to help guide treatment for other problems that can develop.

Breast milk culture

If you have an infection that isn't improving with treatment, your doctor may do a breast milk culture. To provide a sample for a culture, you will squeeze a small sample of milk from the affected breast onto a sterile swab. The culture results help your doctor confirm a diagnosis and to find out the specific bacteria that are causing the infection.

In some cases, it takes more than one round of antibiotics to clear a breast infection. If you have not been responding to antibiotic treatment, culture results may be used to find out the most effective antibiotic for you.

Abscess

Sometimes a pocket of pus (abscess) forms in the reddened area of the breast. If an abscess is too deep to examine by touching it, your doctor may use a breast ultrasound to examine it. Ultrasound can also be used to guide a needle to an abscess that needs to be drained of fluid. A culture of the abscess fluid is usually done to identify the infecting organism.