Review Question - QID 218533

This patient who is otherwise healthy and presents with unchanged blue-grey evenly pigmented patches in the back most likely has congenital dermal melanocytosis (previously “Mongolian spots”). These lesions usually spontaneously regress by 1 to 2 years of age and can be managed by observation alone.

Congenital dermal melanocytosis is the most common pigmented lesion in newborns. It is noted in 85-100% of Asian neonates, 60% of Black neonates, and fewer than 10% of White neonates. It typically presents with a blue-grey pigmented patch with ill-defined borders in the sacral-gluteal or shoulder areas. These lesions are benign and usually regress by the first or second year of life. Management is observation. However, these lesions should be carefully documented on initial physical examination to avoid confusion with bruises from non-accidental trauma in future clinical encounters.

Onayemi et al. studied the prevalence of congenital dermal melanocytosis in children in Nigeria. The authors found that 44.7% of the 369 children assessed in the study were noted to have congenital dermal melanocytosis. The authors recommend that clinicians observe these findings over time to help distinguish benign findings from child abuse.

Figure/Illustration A demonstrates a child with congenital dermal melanocytosis. The characteristic evenly pigmented, blue-grey patches in the sacral-gluteal region, as well as the rest of the back, are indicated by red arrows.

Incorrect Answers:
Answer 1: Cleaning the newborn with soap and water daily is the treatment of choice for neonatal acne (neonatal cephalic pustulosis). This usually presents in neonates around 3 weeks of age with inflammatory papules and pustules in the face without comedonal lesions.

Answer 2: Contacting child protective services is important in cases of suspected child abuse. Some findings associated with child abuse include burns in the shape of a hot object, metaphyseal fractures, rib fractures, and retinal hemorrhage. In this case, there is no evidence of child abuse, and the findings of congenital dermal melanocytosis were already present at birth.

Answer 3: Excisional biopsy is required in cases of suspected melanoma. However, the even coloration, flat appearance, and typical location of the findings in this child are much more suggestive of congenital dermal melanocytosis. By contrast, typical findings of melanoma include lesion asymmetry, irregular borders, variegated color, larger diameter, and evolution over time. Observation alone is sufficient in the management of congenital dermal melanocytosis.

Answer 5: Propranolol can be used to treat superficial hemangiomas (strawberry hemangiomas) that are present in sensitive areas, such as around the eyes. Unlike congenital dermal melanocytosis, superficial hemangiomas tend to be bright-red papules, nodules, or plaques that are raised above normal skin.

Bullet Summary:
Congenital dermal melanocytosis presents with blue-grey evenly pigmented patches in the sacral-gluteal region that can be managed with observation alone.