Non-puerperal mastitis (NPM), which includes mammary duct ectasia (MED)/periductal mastitis (PDM) and granulomatous lobular mastitis (GLM), is a group of inflammatory conditions occurring in women outside of the breastfeeding period. These diseases typically exhibit a self-limiting course. In recent years, the incidence of NPM has shown a significant upward trend. The peak age of onset is 20 to 40 years.
Etiology
The exact causes of NPM remain unclear. Possible factors include mammary duct ectasia, nipple inversion or deformities, and infections caused by specific bacteria.
Clinical Manifestations
NPM primarily presents with breast pain and lumps. Associated symptoms often include nipple inversion and yellow serous or purulent nipple discharge. In some cases, patients may develop abscesses that, upon rupture, can lead to complications such as mammary fistulas, sinus tracts, or ulcers. These conditions tend to recur and can persist for extended periods without resolution. Local symptoms are usually prominent, while systemic inflammatory responses tend to be mild. Occasionally, skin erythema or joint swelling may occur as concomitant manifestations.
Treatment
Treatment options include medical therapy and surgical intervention. Medications such as antibiotics, glucocorticoids (e.g., methylprednisolone), and anti-tuberculosis drugs may be employed. For cases with stable and localized lumps without evident signs of acute inflammation, surgical treatment may be considered. Complete and thorough excision of the lesion is recommended, with appropriate extension of the excision to help reduce the likelihood of recurrence.
For patients presenting with abscess formation, incision and drainage procedures are performed to manage the abscess.