Lactational mastitis is a localized, painful inflammation of the breast associated with fever and malaise that occurs in breastfeeding women. Management of lactational mastitis will be reviewed here. The management of a breast abscess and other inflammatory breast disorders are reviewed elsewhere. (See "Breast abscess" and "Breast cellulitis: Clinical manifestations, diagnosis, and management" and "Mastitis and other skin disorders of the breast in adults".)
Lactational mastitis has been estimated to occur in 2 to 10 percent of breastfeeding women . The risk of mastitis requiring hospitalization is much lower. In one retrospective study, 127 women from a cohort of 136,459 new mothers were hospitalized for mastitis, resulting in an incidence of 9 per 10,000 deliveries .
Women who develop mastitis while lactating usually have breastfeeding problems (figure 1) . Risk factors for lactational mastitis include an episode of mastitis with a previous child, severe prolonged unilateral engorgement, poor milk drainage and nipple excoriation or cracking . Organisms gain access to the stagnant milk through the nipple and this results in mastitis, which, if left untreated, can progress to local abscess formation. (See "Common problems of breastfeeding and weaning" and "Breast abscess".)
CLINICAL MANIFESTATIONS AND DIAGNOSTIC EVALUATION
The diagnosis of mastitis is made clinically. Lactational mastitis typically presents as a hard, red, tender, swollen area of one breast associated with fever >38.3ºC in a nursing mother. Other systemic complaints may variably include myalgia, chills, malaise, and flu-like symptoms. In the early stages of breast infection the presentation can be subtle with few clinical signs, while patients with advanced infection may present with a large area of breast swelling with overlying skin changes (eg, erythema). Reactive lymphadenopathy can also cause axillary pain and swelling. Septic shock rarely occurs.
In a lactating woman, severe engorgement can be distinguished from mastitis because engorgement is bilateral with generalized involvement . Mastitis associated with erythema and edema during is uncommon and a diagnosis of inflammatory breast cancer must be excluded. (See "Inflammatory breast cancer: Clinical features and treatment", section on 'Clinical presentation and diagnostic evaluation'.)