An unusual case of transient neonatal pustular melanosis: a diagnostic puzzle

A newborn's skin may exhibit a variety of changes during the first weeks of life, and rashes are extremely common in the neonatal period, representing a significant source of parental concern. In particular, a variety of skin eruptions can present as pustules. Most of them are innocuous and self-limiting, while others can be the manifestation of an infectious disease or even indicative of serious underlying disorders. Transient neonatal pustular melanosis is an uncommon vesiculopustular rash characterized by small pustules on a non-erythematous base, noted at birth or during the first day of life, without systemic symptoms. The lesions rupture spontaneously, leaving hyperpigmented macules that usually fade within few weeks. Clinical recognition of this disease can help physicians avoid unnecessary diagnostic testing and treatment for infectious etiologies because no specific therapy is recommended. The clinical aspect and time of onset are generally sufficient to make the correct diagnosis. Nevertheless, peculiar clinical presentations may require additional work-up to rule out life-threatening conditions, and dermatological consultation and histological examination are required for the final diagnosis.

We report an exceedingly unusual presentation of transient neonatal pustular melanosis, suggesting the importance of a systematic diagnostic approach to allow a confident recognition of this benign condition.