Diagnosis and Management of Cutaneous Mastocytosis and Congenital Melanocytic Nevi in Children

Clinical Presentation and Diagnosis

The American Academy of Pediatrics recommends that children with multiple red to brown to yellow lesions measuring a few millimeters to 1-2 cm in diameter be evaluated for urticaria pigmentosa, a condition that presents as macules, plaques, or nodules and commonly affects the trunk and extremities 1
A key diagnostic feature of urticaria pigmentosa is Darier's sign, which is characterized by wheal and flare formation, often accompanied by erythema, swelling, and pruritus, after stroking or rubbing the lesions 1
The American Academy of Dermatology notes that congenital melanocytic nevi (CMN) have an incidence of <1% to 3.6% and present as shades of brown and black within macules, papules, patches, or plaques, with the "classic" subtype showing brown and black coloration, and the "blue" subtype appearing as gray-blue patches or plaques 2

The American Academy of Pediatrics recommends that children with confirmed urticaria pigmentosa be reassured that the condition typically resolves spontaneously by puberty and rarely involves systemic disease, and that they should avoid triggers that cause mast cell degranulation, such as vigorous rubbing, hot baths, and certain medications 1
The American Academy of Dermatology suggests that children with multiple CMN (>1 lesion) are at highest risk for neurocutaneous melanosis and warrant MRI screening of the brain and spine, and that the projected adult size of each lesion should be documented, as those >40 cm carry higher melanoma risk 2

The American Academy of Pediatrics recommends that children with uncertain diagnosis after initial evaluation be referred to pediatric dermatology, and that immediate referral is warranted if the child experiences systemic symptoms, such as recurrent flushing, wheezing, syncope, or gastrointestinal bleeding 1
The American Academy of Dermatology suggests that children with confirmed multiple CMN be referred for consideration of MRI, particularly with >1 lesion or satellite nevi 2