Mastitis pathophysiology

Terminology
Depending on appearance, symptoms, aetiological assumptions and histopathological findings a variety of terms has been used to describe mastitis and various related aspects.


 * galactopoiesis: milk production


 * secretory disease: aberrant secretory activity in the lobular and lactiferous duct system, believed to be the most frequent factor causing galactophoritis. The secretions may be milk like or apocrine luminal fluid.


 * retention syndrome (aka retention mastitis): accumulation of secretions in the ducts with mainly intraductal inflammation.


 * galactostasis: like retention syndrome where the secret is known to be milk.


 * galactophoritis: inflammation of the lobular and lactiferous duct system, mainly resulting from secretory disease and retention syndrome.


 * plasma cell mastitis: plasma cells from the intraductal inflammation infiltrate surrounding tissue.


 * duct ectasia: literally widening of lactiferous ducts - relatively common finding in breast exams, increase with age. Strongly correlated with cyclic and very strongly with noncyclic breast pain. Correlation with mastitis is of anecdotal quality and has been questioned by recent research.


 * duct ectasia syndrome: in older literature this was used as synonym for nonpuerperal mastitis with recurring breast abscess, nipple discharge and possibly associated fibrocystic condition with blue dome cysts. Recent research shows that duct ectasia is only very weakly correlated with mastitis symptomes (inflammation, breast abscess). The use of the terms Duct Ectasia and Duct Ectasia Syndrome is inconsistent throughout the literature.


 * squamous metaplasia of lactiferous ducts: cuboid cells in the epithelial lining of the lactiferous ducts transform (squamous metaplasia) to squamous epithelial cells. Present in many cases of subareolar abscesses.


 * subareolar abscess: abscess bellow or in close vicinity of the areola. Mostly resulting from galactophoritis.


 * retroareolar abscess: deeper (closer to chest) than the lobular ductal system and thus deeper than a subareolar abscess.


 * periductal inflammation (aka periductal mastitis): inflammation infiltrated tissue surrounding lactiferous ducts. Almost synonym for subaerolar abscess. May be just a different name for plasma cell mastitis.


 * fistula: fine channel draining an abscess cavity


 * Zuska's disease: periareolar abscess associated with squamous metaplasia of lactiferous ducts. Some authors also associate this with nipple discharge.