What can cause a dry, raised, rough rash without erythema or edema and a keratotic look on the forehead of a one-month-old premature infant born at 34 weeks gestation?

Differential Diagnosis of Dry, Raised, Rough, Keratotic Rash on Forehead in a One-Month-Old Premature Infant

This presentation is most consistent with seborrheic dermatitis, which commonly affects the scalp and face of infants in the first months of life, presenting as scaling and crusting without significant erythema. 1, 2, 3

Primary Diagnostic Considerations

Seborrheic Dermatitis (Most Likely)

• Presents as scaling on the scalp and face, including the forehead, in the first months of life 3
• The keratotic, rough appearance without erythema or edema fits this diagnosis well 2
• Extremely common in infants and can appear dry and scaly rather than inflammatory 1, 3
• Does not typically cause significant erythema, which distinguishes it from atopic dermatitis in this age group 3

Atopic Dermatitis (Less Likely at This Age)

• While atopic eczema can affect the face and forehead in children under 4 years, it typically presents with more erythema and pruritus 1
• The absence of erythema and edema makes this less likely 1
• Onset in the first two years of life is characteristic, but presentation at one month without inflammation is atypical 1
• In infants under 4 years, atopic dermatitis more commonly affects the cheeks rather than isolated forehead involvement 1

Milia or Miliaria (Possible but Different Presentation)

• These result from immaturity of skin structures and present as tiny vesicles or papules, not rough keratotic patches 2, 3
• Typically resolve spontaneously without the rough, raised texture described 2

Conditions to Rule Out

Transient Neonatal Rashes (Unlikely)

• Erythema toxicum neonatorum appears in the first 48 hours of life with erythematous macules, papules, and pustules—not dry keratotic lesions 4, 2, 5
• Resolves spontaneously within one week, making it unlikely at one month of age 4, 5

Infectious Causes (Should Be Excluded)

• Candida infection would typically show more erythema and satellite lesions 3
• Bacterial or viral infections would present with systemic signs or more inflammatory changes 2

Prematurity-Specific Considerations

Premature infants born at 34 weeks have thinner epidermis with poorly formed stratum corneum barrier compared to full-term infants 6

• This increases susceptibility to skin compromise and irritation 6
• However, premature infants may paradoxically show better skin integrity in some areas due to protective NICU practices 6
• The skin barrier continues to mature over the first weeks to months of life 6

Management Approach

Initial Treatment for Seborrheic Dermatitis

• Apply emollients regularly, especially after bathing, to maintain skin barrier function 7
• Use gentle shampooing and remove scales with a soft brush after applying mineral oil or petrolatum 3
• For severe or persistent cases, consider tar-containing shampoo or topical ketoconazole 2, 3

When to Escalate Care

• If the rash worsens, develops significant erythema, or shows signs of secondary infection (crusting, weeping), bacterial or fungal cultures should be obtained 1
• Failure to respond to basic emollient therapy within 2-3 weeks warrants consideration of other diagnoses 1
• Development of systemic symptoms requires immediate evaluation for infection 2

Critical Pitfalls to Avoid

• Do not assume all facial rashes in premature infants are benign—always assess for signs of infection or systemic illness 2
• Avoid using high-potency topical corticosteroids on infant facial skin, as this can cause skin atrophy 7
• Do not overlook the possibility of contact dermatitis from skin care products used in the NICU setting 6
• Premature infants with early and frequent stool contact are at higher risk for skin compromise and may need prophylactic interventions 6