Sonographic features of neonatal mastitis and breast abscess

Abstract

Neonatal mastitis and breast abscess are unusual diseases that should be appropriately treated with antibiotics and drainage to avoid generalized sepsis, breast hypoplasia, and scarring. US is useful in distinguishing mastitis from breast abscess and guiding treatment options.

Sonographic features of physiologic neonatal breast enlargement

“…[7] It usually occurs under 5 weeks of age with peak incidence at 3 weeks of age. [48910] It is mostly unilateral with no predilection for right or left breast. In the first 2 weeks of life, it is found in equal frequency in males and females but after 2 weeks of life it is twice more likely in female infants.…”

“…However, when the causative organism is a gram negative bacteria, hematogenous spread is a possible explanation. [810] Typical presentation of neonatal mastitis can include unilateral swelling, erythema, warmth, tenderness and induration in the absence of systemic signs of infection. Occasionally, surrounding skin changes and axillary lymph node involvement can occur.…”

“…[7] If left untreated, neonatal mastitis can progress to breast abscess formation and rarely lead on to cellulitis, fasciitis, osteomyelitis, brain abscess and generalized sepsis. [48]…”

Pediatric and Adolescent Breast Masses: A Review of Pathophysiology, Imaging, Diagnosis, and Treatment

“…The majority of cases are found in girls, and common pathogens include Staphylococcus aureus (> 75% of cases), gram-negative bacilli, group A Streptococcus species, and Enterococcus species [13]. Neonatal mastitis is rare and is presumed to be caused by mucous membrane and skin pathogens gaining access to the hormonally stimulated infant breast tissue through the nipple or ducts [14]. Pediatric…”

“…Ultrasound is helpful in differentiating mastitis from abscess [14]. At sonography, mastitis can show both decreased echogenicity (early phlegmon) or increased echogenicity (usually due to edema of the fatty tissue).…”