A 3-month-old with a blistering plaque.

Cutaneous Mastocytosis is not an uncommon condition in the pediatric setting. The eruption can have multiple clinical presentations. We present a case of a 3-month-old child with a solitary mastocytoma who was initially diagnosed with recurrent bullous impetigo. Solitary mastocytoma can present as a blister. Although bullous impetigo is a common diagnosis in children and it would be tempting to make that diagnosis in the presence of a positive skin swab culture, clinicians always have to be mindful of secondary impetiginization of another primary skin disease process.