Rarely a neonate or young infant may present with mastitis.

Pathogenesis: Neonatal breast enlargement (gynecomastia) may develop secondary to prolactin secretion by the pituitary in response to falling estrogen levels. Obstruction of breast ducts may be followed by local infection.


Clinical findings:

(1) mastitis (with erythema, swelling and pain) and/or breast abscess

(2) axillary lymphadenopathy


It is more common in females.


Causative pathogens include:

(1) Staphylococcus aureus

(2) Group B streptococci

(3) Gram-negative enteric bacteria

(4) anaerobic organisms


Aggressive antibiotic therapy is effective if started immediately upon diagnosis. An abscess may require incision and drainage.


Less than 2% of patients develop sepsis, shock or necrotizing infection (Kaplan).

To read more or access our algorithms and calculators, please log in or register.