What is the hallmark of transient neonatal pustular melanosis?

The hallmark of transient neonatal pustular melanosis is the presence of neutrophils. This condition is characterized by the appearance of small, superficial vesicles or pustules on the newborn's skin, which can rupture and lead to pigmented macules. The lesions are associated with an inflammatory response, prominently featuring neutrophils, which are a type of white blood cell that play a crucial role in immune defense.

This immune response indicates that the pustular lesions are not due to an infectious process but rather a reaction to external stimuli or normal skin maturation in neonates. Understanding the role of neutrophils in this condition helps differentiate it from other skin eruptions, allowing for accurate diagnosis and management in neonatal care. The benign nature of transient neonatal pustular melanosis also means that while the presence of neutrophils is common, the lesions typically resolve without intervention, reinforcing the distinction of this condition among neonatal skin disorders.