Management of Erythema Toxicum Neonatorum in a Healthy Term Newborn
Erythema toxicum neonatorum (ETN) in a healthy term newborn presenting on day 3 requires no treatment—reassure parents that this is a benign, self-limited rash that will resolve spontaneously within one week without sequelae. 1
Clinical Recognition and Diagnosis
ETN is a common neonatal dermatologic disorder affecting approximately 50% of term newborns, typically appearing within the first 48 hours of life (though onset up to 10 days has been documented). 1, 2 The characteristic lesions include:
- Erythematous macules, wheals, papules, and pustules distributed on the trunk and proximal extremities 1
- Lesions that spare the palms and soles 3
- Pustules that, if sampled, show predominance of eosinophils on Wright stain 2, 3
The diagnosis is clinical and requires no laboratory testing or skin biopsy in typical presentations. 1
Management Algorithm
For Typical Presentation (Day 3, Healthy Term Infant):
No intervention is required. 1 The management consists solely of:
- Parental reassurance that this is a benign physiologic process 1
- Observation only—the rash resolves spontaneously within 5-7 days without treatment 1
- No topical or systemic therapies are indicated 1
When to Consider Diagnostic Testing:
Diagnostic workup is only necessary when the presentation is atypical and you need to exclude infectious or serious pustular dermatoses: 2
- Onset after day 10 of life 2
- Systemic signs of illness (fever, lethargy, poor feeding) 2
- Ill-appearing infant or signs of sepsis 2
- Pustules on palms and soles (suggests alternative diagnosis) 3
If testing is performed in atypical cases, obtain: 2
- Wright stain of pustule contents (should show eosinophils, not bacteria)
- Complete blood count (may show peripheral eosinophilia up to 10%)
- Blood and pustule cultures if sepsis is a concern (will be negative in ETN)
Critical Pitfalls to Avoid
Do not perform a septic workup or initiate antibiotics in a well-appearing term infant with typical ETN presenting on day 3. 1 The key distinguishing features that confirm benign ETN rather than infection are:
- Well-appearing infant with normal vital signs and feeding 1, 2
- Characteristic distribution sparing palms and soles 3
- Timing within first week of life 1
Do not confuse ETN with serious neonatal pustular conditions that require treatment: 3
- Neonatal herpes simplex (vesicles, often grouped, may have systemic illness)
- Bacterial sepsis with pustulosis (ill-appearing infant)
- Congenital candidiasis (diffuse pustules including palms/soles)
Pathophysiology Context
While the exact etiology remains unclear, ETN represents an accumulation and activation of immune cells (eosinophils, dendritic cells, neutrophils) with expression of proinflammatory cytokines and adhesion molecules. 4 This immunologic activity is a physiologic adaptation process in the newborn skin and does not indicate infection or allergy. 4, 5 Understanding this helps explain to parents why no treatment is needed—the infant's immune system is simply adjusting to extrauterine life. 1
Follow-Up
No specific follow-up is required for ETN. 1 Parents can be instructed to continue routine newborn care and that the rash will fade completely by 2 weeks of age at most. 1, 2