Newborns often present with skin findings, many of which are benign. In general, our approach to these patients depends on various factors:
- Sick versus not sick
- Prenatal risk factors
- Vital signs
- Exam findings apart from the skin
Harlequin Color Change
- Affects 10% of full-term infants, and even more common in premature infants
- Typically presents on day of life 2-5, and up to 3 weeks of life
- Often sudden onset (30 sec to 20 min)
- Resolves with increased tone
- Mechanism: unclear, but thought to be immaturity of the hypothalamic center leading to dilation of peripheral blood vessels
- Examples:
Cutis marmorata
- Appearance: reticulated bluish mottling; disappears with warming
- Mechanism: dilation of capillaries and small venules in response to cold
- May recur into early childhood; in patients with persistent mottling despite warming, consider cutis marmorata telangiectatica congenita
- Examples:
Erythema Toxicum Neonatorum
- Very common pustular eruption, affecting 40-70% of term neonates, typically appearing on DOL 2-3
- Appearance: erythematous small macules/papules/pustules, surrounded by a blotchy area of erythema, most often on the face, trunk, and proximal extremities
- Board pearl: lesions contain eosinophils
- Examples:
Transient Neonatal Pustular Melanosis
- Appearance: vesiculopustular rash affecting all bodily areas; lesions lack surrounding erythema; lesions rupture easily, leaving behind a hyperpigmented macule
- Fades over 3-4 weeks
- Board pearl: lesions contain PMNs
- Examples:
Neonatal cephalic pustulosis
- Previously called acne neonatorum, which is a misnomer because
- Appearance: pustular eruption arising on the face/scalp, usually in the 3rd week of life
- Mechanism: likely a reaction to Malassezia
- Examples:
Milia
- Very common finding, affecting around half of newborns
- Appearance: pearly white or yellow papules
- Mechanism: retention of keratin
- Usually spontaneously regress within the first month
- May occur on the hard palate (Bohn’s nodules) or gum margins (Epstein’s pearls)
- Examples:
Miliaria
- Very common, affecting 40% of infants
- Mechanism: sweat retention caused by partial closure of eccrine structures
- Milaria crystalina = superficial duct closure
- Milaria rubra = heat rash, caused by deeper level of sweat gland obstruction
- Avoid overheating, excess clothing
- Examples:
Seborrheic Dermatitis
- Appearance: greasy scale, typically on scalp (aka cradle cap) but can also affect face, ears, neck, and diaper area
- Examples:
PIGMENTED Birthmarks
Congenital Melanocytic Nevi
- Mechanism: disrupted migration of melanocyte precursors in the neural crest
- Appearance: brown to black nevi that are mostly flat but can be slightly raised
- Management depends on size
- Examples:
Dermal Melanosis
- Most common on the lower back/buttocks in patients of Asian, Hispanic, and Native American descent
- Typically fade by 2 years of age
- Examples:
Vascular Birthmarks
Hemangioma
- Less common, affecting 1-2% of newborns
- May develop anytime in first few months of life, but tend to involute/disappear after infancy
- Most often cosmetically bothersome, but may be clinically concerning depending on size and location
- Scoring sheet (high score suggests need to see a vascular anomaly specialist, ideally within 4-6 weeks of life)
- Management may be watchful waiting, topical timolol (low risk = local therapy), or PO propranolol (high risk = systemic therapy)
- Examples:
Nevus Flammeus
- Commonly confused with nevus simplex
- Uncommon: 0.1-0.3% of newborns
- Appearance: typically unilateral or segmental distribution that often respects the midline and typically found on the head/neck but may be located at any part of the body
- Lesions do not regress; they grow in proportion to the child’s growth, becoming thicker and darker during adulthood
- Associated with multiple syndromes: Sturge-Weber, Klippel-Trenaunay, Parkes-Weber, Proteus, Beckwith-Wiedemann, etc.
- Examples:
Nevus Simplex
- Commonly confused with nevus flammeus
- Very common, affecting 40-60% of newborns
- Present at birth, most commonly at the forehead, glabella, upper eyelids, and nape
- Less common sites: back, nose, upper/lower lip, and occipital/parietal scalp
- Appearance: lesions vary in color from pink to red, often with indistinct borders
- Partially/completely blanchable
- More prominent with crying, vigorous activity, or changes in ambient temp
- Most lesions fade spontaneously with 1-2 years
- Examples:
Blog post based on Med-Peds Forum talk by Becca Raymond-Kolker, PGY2, and Maya Tsao-Wu, PGY1