Breast abscess

Background

Can occur in both lactating and nonlactating If breastfeeding, typically starts as mastitis and progresses to abscess Types of nonlactational (central, peripheral or skin)

• Central - periductal mastitis
• Peripheral - less common (DM, RA, trauma, steroids)
• Skin

Pathogens: staphylococcus aureus (MRSA incidence increasing), enterococci, bacteroides, strep pyogenes

Clinical Features

Erythema Warmth Tenderness Fluctuant localized mass +/- Fever Risk factors: smoking, obesity

Differential Diagnosis

• Mastitis
• Cellulitis
• Malignancy (i.e inflammatory breast cancer)
• Clogged duct
• Galactocele

Evaluation

Workup

• Blood cultures if septic

Diagnosis

Clinical diagnosis POCUS to evaluate for fluid pocket vs cellulitic changes Formal breast US if malignancy concern

Management

Drainage:

• Needle aspiration

- Safe in the ED if no signs of necrosis/ ischemic skin - Anesthetize with lidocaine 1% with epi - Can use 18g needle to aspirate - Send aspirate for culture to tailor antibiotics

• Surgical

- Failure to respond to I&D in the ED - Signs of skin ischemia/ necrosis or complex abscess - Non responsive to antibiotics

Antibiotics Outpatient No MRSA risk factors: - Dicloxacillin 500mg QID OR - Cephalexin 500mg QID OR - beta lactam allergy: Clindamycin 300-450mg TID MRSA risk - Trimethoprim-sulfamethoxazole DS 1-2 tabs BID - Clindamycine 300-450mg TID Inpatient - Vancomycin IVPB

Needs follow up in 2-3 days for wound check (sometimes needs to be re-drained) Referral to breast specialist (breast surgeon,

Harbor UCLA breast abscess pathway

References

Dixon, J Michael. “Primary Breast Abscess.” UpToDate, 11 Dec. 2024, www.uptodate.com/contents/primary-breast-abscess. Losifescu, Sarah. “Mastitis and Breast Abscesses.” emDocs, 5 Aug. 2020, www.emdocs.net/mastitis-and-breast-abscesses/.