Neonatal mastitis

This page is for pediatric patients. For adult patients, see: mastitis (also for adolescent patients)

Background

• Uncommon soft-tissue infection of the breast tissue in children <2mo of age
• More common in females than in males
• More commonly unilateral than bilateral
• Reported confirmed sources have included MSSA and MRSA, and rarely acinetobacter, e. coli, and proteus mirabilis
• Reported sequelae have included brain abscess and osteomyelitis

Clinical Features

Right neonatal mastitis in a female infant

Right neonatal mastitis in a female infant

• Presentation within 2 months of life with redness overlying the breast tissue and/or possibly purulent discharge from one, or rarely both, nipples.
  • The affected breast may be apparently tender to the touch on exam.
  • Palpable fluctuance suggestive of abscess may or may not be present.
• Parents may also report other concurrent, but nonspecific concerns such as
  • Poor feeding
  • Increased fussiness
  • Inconsolability
  • Subjective or measured fevers
  • Lethargy

Differential Diagnosis

• Cellulitis
• Necrotizing soft tissue infections
• Pediatric fever of uncertain source
• Sepsis (peds)
• Physiologic breast hypertrophy (Neonatal Mastauxe/Giant Mastauxe)

Neonatal Rashes

• Acne
• Atopic dermatitis
• Candidiasis
• Contact dermatitis
• Diaper dermatitis
• Erythema toxicum neonatorum
• Impetigo
• Mastitis
• Milia
• Miliaria
• Mongolian spots
• Omphalitis
• Perianal streptococcal dermatitis
• Psoriasis
• Pustular melanosis
• Seborrheic dermatitis
• Sucking blisters
• Tinea capitis

Evaluation

Febrile or Ill-Appearing

• Serious bacterial infection (SBI) workup for pediatric fever of uncertain source
  • Neonatal Mastitis should not be relied upon as a diagnosis to exclude other SBI in the febrile or ill-appearing infant
• Consider sepsis alerts and bundles per local protocol

Afebrile, Well-Appearing

• Head-to-toe physical examination
  • May have varying degrees of normal breast tissue hypertrophy bilaterally, but lack of breast tissue hypertrophy is not specific against the diagnosis.
• Laboratory workup to include
  • Complete blood count
  • Basic metabolic panel
  • Consider blood cultures
  • Consider sending swabs for local site cultures
    • Catheterized urine sample and LP are not required

• Imaging
  • POCUS assessment for abscess in the ER has not been studied
  • Radiology ultrasounds may be ordered at consultant/admitting provider request or per local protocol, may help to identify abscess and guide surgical decision making

Diagnosis

• Clinical diagnosis which does not require imaging or microbiological confirmation to plan for disposition or begin treatment.
• Other diagnoses, such as sepsis, disseminated cellulitis, or necrotizing fasciitis may be made concurrently and should be managed appropriately.

Management

• Inpatient (most)
  • IV Nafcillin (first choice)
    • Antibiosis should focus on anti-staphylococcal coverage with consideration given for local MRSA proliferation.
  • Add additional coverage for MRSA if indicated
• Outpatient (rare)
  • Consider local antibiotic resistance patterns

Disposition

• Should generally be admitted for antibiosis and close monitoring in the NICU.
  • Though mortality is very low, severe sequelae have been documented.

See Also

• Pediatric fever of uncertain source
• Sepsis (peds)
• Mastitis

External Links

Pediatric EM Morsels: Mastitis