Mastitis, Puerperal

Key Features

• Occurs sporadically in nursing mothers

• Staphylococcus aureus is usually the causative agent

• Women nursing for the first time and those with difficulty breastfeeding appear to be at greatest risk; strategies aimed at preventing mastitis have been unsuccessful

• Nursing from the infected breast is safe for the infant, but inflammation of the nipple may complicate latching

• Rarely, inflammatory carcinoma of the breast can be mistaken for puerperal mastitis

Clinical Findings

• Frequently begins within 3 months after delivery

• May start with an engorged breast and a sore or fissured nipple

• Cellulitis is typically unilateral with the affected area of breast being red, tender, and warm

• Fever and chills are common

Diagnosis

• Clinical

• Failure to respond to usual antibiotics within 3 days may represent an organizing abscess or infection with a resistant organism

• Ultrasonography of the breast can help confirm presence of an abscess

Treatment

• Antibiotics effective against penicillin-resistant staphylococci should be given (dicloxacillin 500 mg orally every 6 hours or a cephalosporin for 10–14 days)

• Regular emptying of the breast by nursing or by using a mechanical suction device

• The risk of abscess formation is increased when the causative organism is methicillin-resistant S aureus (MRSA)

• Aspiration or surgical evacuation is usually required to treat an abscess

• Changing antibiotics based on culture sensitivity (to vancomycin or trimethoprim-sulfamethoxazole, for example) is useful, especially if the clinical course is not improving appropriately