Neonatal Acne

Neonatal acne is the presence of inflammatory papules and pustules on the face of newborns, typically on the cheeks, nose and forehead, with onset at 2 to 4 weeks of age; affects up to 20 percent of newborns, more in boys.

• Cause: maternal and neonatal androgen stimulation of sebaceous glands, with reaction to Malassezia yeast species (many cases are best classified as neonatal cephalic pustulosis). True comedones are usually absent in the neonatal period.
• Distinguish:
  • Neonatal acne (cephalic pustulosis): papules and pustules on the face without comedones; onset 2 to 4 weeks; resolves by 4 to 6 months.
  • Infantile acne: onset 3 to 6 months (up to 12 months), with comedones, nodules and cysts; may persist for years and scar; may indicate endocrine disorder when severe.
  • Milia: tiny white keratin cysts on the nose and cheeks, present at birth.
• Risk factors: maternal acne, maternal medications (corticosteroids, androgens, lithium, phenytoin, phenobarbital), family history of severe acne.
• Self-limited and harmless; scarring is rare.

• Small red papules and pustules on the cheeks, forehead, nose and chin, sometimes eyelids, neck and scalp; the child is well and thriving; rash may fluctuate with heat, crying and spit up contact; no systemic features.
• Examination: no fever, no vesicles, no scale, healthy growth; check for virilisation signs (clitoromegaly, enlarged penis, pubic hair), hirsutism and rapid growth in infantile acne.
• Red flags: widespread or severe nodulocystic acne, comedones with cysts, onset before 2 weeks or after 6 months, virilisation, advanced bone age, rapid growth, persistent acne beyond 12 months, fever, blistering, vesicles (herpes simplex), pustules with systemic upset (staphylococcal infection), erythema toxicum (day 2 to 5 rash with eosinophils), signs of candida, drug exposure.

• Clinical diagnosis from appearance and age.
• Bacterial culture, potassium hydroxide preparation or herpes PCR if pustules persist with atypical features or a systemic upset.
• Endocrine evaluation for severe or persistent infantile acne with virilisation or growth acceleration: testosterone, free testosterone, DHEAS, 17-hydroxyprogesterone, luteinising hormone, follicle stimulating hormone, bone age.
• Differentials: milia, miliaria, erythema toxicum neonatorum, folliculitis, candidiasis, impetigo, herpes simplex, transient neonatal pustular melanosis, atopic dermatitis, seborrhoeic dermatitis, drug eruption.

• Reassure parents that it is common, harmless, not caused by poor hygiene or breast milk, and will clear without scarring.
• Gentle skincare: wash the face with plain warm water once or twice daily and pat dry; avoid scrubbing, squeezing, oils, greasy creams, lotions and harsh soaps; wash off milk or saliva from the face promptly; use soft cotton clothing and bedding.
• Mild cases (the majority) need no treatment; expect resolution within weeks to 4 months.
• Persistent or Malassezia associated lesions: ketoconazole 2 percent cream applied to the affected skin once or twice daily for 2 to 4 weeks, avoiding eyes.
• Moderate persistent lesions or infantile acne: benzoyl peroxide 2.5 percent gel or lotion applied thinly once daily at night, increasing to twice daily if tolerated (irritation, bleaching of fabrics); topical erythromycin 2 percent gel twice daily or clindamycin 1 percent gel; adapalene 0.1 percent gel or tretinoin 0.025 percent cream once daily in resistant infantile acne (specialist advice).
• Severe nodulocystic infantile acne: erythromycin 25 to 50 mg/kg/day orally in 2 to 3 divided doses for 3 to 6 months by a specialist (avoid tetracyclines under 8 years); isotretinoin 0.5 to 1 mg/kg/day orally only in exceptional cases by paediatric dermatologists.
• Avoid topical corticosteroids on the face (steroid induced acne and rosacea like eruption).
• Treat superimposed infection: mupirocin 2 percent ointment twice daily for 5 days, or oral flucloxacillin 12.5 to 25 mg/kg four times daily for 5 to 7 days for extensive pustulosis.
• Review in 4 to 6 weeks; refer to a paediatric dermatologist for acne persisting beyond 6 months, scarring, severe or nodulocystic lesions, or an endocrinologist for signs of androgen excess.