Differential Diagnosis of Epidermal Nevi of Scalp in a 5-Month-Old Baby
Single Most Likely Diagnosis
- Epidermal Nevus: This is the most likely diagnosis given the presentation of a skin lesion on the scalp of a baby. Epidermal nevi are benign growths that can appear as linear or patchy areas of thickened skin, often present at birth or early infancy.
Other Likely Diagnoses
- Congenital Melanocytic Nevus: Although less common than epidermal nevi, congenital melanocytic nevi can also present as pigmented lesions on the scalp and should be considered in the differential diagnosis.
- Sebaceous Nevus: A type of epidermal nevus, sebaceous nevi can appear on the scalp and have a characteristic yellowish hue due to the presence of sebaceous glands.
- Infantile Hemangioma: While typically presenting as a red, vascular lesion, infantile hemangiomas can sometimes appear on the scalp and may be considered in the differential, especially if the lesion has a vascular component.
Do Not Miss Diagnoses
- Meningocele or Encephalocele: Although rare, these conditions involve protrusions of the meninges or brain tissue through a defect in the skull and can sometimes be mistaken for scalp lesions. It is crucial to rule out these conditions due to their significant implications for the baby's health and potential need for surgical intervention.
- Langerhans Cell Histiocytosis: This rare condition can present with skin lesions, among other systemic symptoms, and is important to consider due to its potential for serious complications if left untreated.
Rare Diagnoses
- Nevus Sebaceous of Jadassohn: A specific type of sebaceous nevus that can have a higher risk of developing into basal cell carcinoma later in life, although this is more relevant for long-term follow-up rather than immediate diagnosis in infancy.
- Linear Scleroderma (Morphea): A rare condition that can cause linear or patchy areas of skin thickening, which might be considered in the differential diagnosis of epidermal nevi, especially if there are other signs of scleroderma.
- Incontinentia Pigmenti: A genetic disorder that can cause skin lesions, including those on the scalp, along with other systemic manifestations. It's rare and mostly seen in females due to its X-linked dominant inheritance pattern.