Non-puerperal Breast Actinomycosis: A Case Report

Breast abscesses can be a complication of infectious mastitis or the first presentation of a breast infection, presenting as pain, erythema, and a lump. Actinomycosis is a rare chronic disease caused by anaerobic branched filamentous gram-positive bacteria belonging to the Actinomyces genus. It is usually found in the human mouth, digestive tract, and genital tract but can also cause breast abscesses. Actinomycosis affecting the breast is a rare condition that typically occurs as a secondary infection resulting from a pulmonary infection. It is primary when inoculation occurs through the nipple. This report describes the case of a 48-year-old institutionalized female with periareolar swelling in the right breast that had been evolving for approximately two months. The abscess was drained, and the aspirated material contained Actinomyces neuii, a gram-positive bacterium. Actinomycosis of the breast can manifest as either a sinus tract or mass-like features that closely resemble malignancy. The clinical presentation can pose challenges in distinguishing between primary actinomycosis, mastitis, and inflammatory carcinoma. Treatment consists of drainage with needle aspiration or surgical drainage and antibiotic therapy.