Treatment
Differential Diagnosis
It is important to distinguish mastitis from physiologic breast hypertrophy, which resolves spontaneously. In contrast to mastitis, in physiologic hypertrophy, the breast bud is neither red nor tender. The nipple discharge (if present) in physiologic hypertrophy is milky rather than purulent and does not contain polymorphonuclear white blood cells or bacteria on Gram stain.
Note!
v After the first 48 h of life, the hypertrophied breasts may become engorged, and a form of lactation occurs. The engorgement and edema begin to subside after the second week of life. This phenomenon occurs with or without galactorrhea in 60% of normal newborns.
v Neonatal Milk Production (“Witch's Milk” or galactorrhea) - is milk secreted from the breasts of some newborn infants. Witch's milk is more likely to be secreted by infants born at full term, and not by prematurely-born infants. It occurs in about 5% of newborns and can persist for 2 months though breast buds can persist into childhood. Neonatal milk secretion is considered a normal variation and no treatment or testing is necessary. It is thought to be caused by a combination of the effects of maternal hormones before birth (transplacental hormonal effects - maternal estrogens and possibly endogenous prolactin), prolactin and growth hormone passed through breast feeding and the postnatal pituitary and thyroid hormone surge in the infant.
No randomized controlled studies have evaluated antibiotic regimens for neonatal mastitis.
Recommendations for treatment are based upon the causative pathogens and the response to therapy. Because of the potential for breast abscess, neonates should be treated with parenteral antibiotics guided by Gram stain when available.
Neonatal mastitis be treated initially with parenteral antibiotics if the infant is febrile, ill appearing, has leukocytosis, or is younger than 28 days of age. An intial dose of parenteral antibiotics is also suggested in infants who are afebrile, well appearing, without leukocytosis, and older than 28 days of age, given the potential for progression to abscess in infants who are initially treated orally and the increasing prevalence of community-associated methicillin-resistant S. aureus. The empiric antibiotic choice should be guided by local susceptibility patterns and the Gram stain, if one is available.
If gram-positive cocci are identified, empiric therapy should include coverage for S. aureus eg Clindamycin or Vancomycin.
If gram-negative organisms are identified, empiric therapy should include an aminoglycoside (eg, gentamicin, amikacin) or third-generation cephalosporin (eg, cefotaxime).
If the Gram stain is not available or if no organisms are seen, then therapy should include coverage for S. aureus and gram-negative enteric organisms. Therapy can be altered according to culture results once they are available.
Incision and drainage may be warranted if an abscess is present. Approximately 50% of infants with mastitis develop a breast abscess.
Antibiotics are an important part of therapy, but the cornerstone of treatment is drainage of the abscess. A small abscess in an otherwise stable infant can be initially treated by aspiration alone. For larger or recurrent abscesses or if the infant is ill, a formal incision and drainage is indicated. Typically, incisions are made in the radial direction at some distance of 3-4 mm from the areola above the area of abscess. A periareolar incision is used for cosmetic reasons. In neonates and small children, a 14-gauge needle can be passed from one areola border to the other (through the abscess) and used to pass a vessel loop through the center of the abscess. The vessel loop can then be tied in a loop to serve as a drain.
The duration of therapy depends upon the clinical response; a total of 7 to 14 days (parenteral and oral) is usually adequate if there are no complications.