Seborrheic%20dermatitis Signs and Symptoms

• A chronic inflammatory skin disorder mostly confined to areas where sebaceous glands are prominent

• Usually caused by inflammatory responses to Malassezia sp proliferation in the stratum corneum
• Malassezia (formerly known as Pityrosporum ovale) infection is common in seborrheic dermatitis

• Have characteristic pattern based on age group

Infants

• Cradle cap: Diffuse or focal scaling and crusting on the vertex of the scalp sometimes accompanied by inflammation
• A greasy, scaly, erythematous papular dermatitis may also involve the face, neck, retroauricular areas, axillae and most of the body
• Flexural folds may be involved, often with a cheesy exudate that manifests as a diaper dermatitis that also may become generalized
• Post-inflammatory pigmentary changes are common
• Oozing, weeping and pruritus are typically absent
• Secondary infection can occur
• May consider Leiner’s disease if lesions becomes widespread and erythrodermic

Young Children

• Tinea amiantacea: One or several patches of dense, plate-like scales, 2-10 cm in size that appear anywhere on the scalp
• Persistent lesions can cause temporary hair loss or produce large, oval, yellow-white plates of scale firmly adherent to the scalp and hair

Adolescents and Adults (Classic Seborrheic Dermatitis)

• Dandruff: Fine, dry, white, non-inflammatory scalp scaling with minor itching
• Scalp changes may vary from diffuse, brawny scaling to focal areas of thick, oily, yellow crusts with underlying erythema
• Severe dermatitis manifests as erythema and scaling at the frontal hairline, the medial aspects of the eyebrows and in the nasolabial and retroauricular folds
• Marginal blepharitis and external auditory canal involvement may be noted
• Red, scaly plaques may also appear in the axillae, inguinal region, gluteal cleft and umbilicus
• On the extremities, seborrheic plaques may be more eczematous and less erythematous and demarcated