ETN is characterized by macular erythema, papules, vesicles, and pustules, and it resolves without permanent sequelae. Similarly, contactants and mechanical irritation have been considered and rejected as etiologies.
Newborn skin appears to respond to any injury with an eosinophilic infiltrate.
Since ETN rarely is seen in premature infants, it is believed that mature newborn skin is required to produce this reaction pattern. Although 1 study found that infants with ETN had an increased risk of atopy, subsequent studies have failed to support this finding. No racial or ethnic predisposition is known. Males and females are affected equally. Rare cases have been reported at birth.