What is a common feature of erythema toxicum neonatorum in newborns?

A common feature of erythema toxicum neonatorum in newborns is the presence of pustules on an erythematous base. This condition typically manifests as small, raised bumps or pustules that develop on a red background, and it often appears within the first few days after birth. The pustules are usually filled with eosinophils, a type of white blood cell, and can vary in size, but they generally resolve without treatment within one to two weeks.

The characteristic appearance helps differentiate erythema toxicum from other skin conditions seen in newborns. For instance, the presence of vesicles is more indicative of other conditions like herpes simplex virus or varicella, while severe itching is not a typical symptom associated with erythema toxicum — in fact, the condition is usually asymptomatic. Flat lesions without elevation might point towards conditions like milia or sebaceous gland hyperplasia rather than erythema toxicum, where pustular lesions with an erythematous background are the hallmark.