Seborrheic dermatitis is a chronic, recurrent skin condition affecting areas with a high concentration of sebaceous glands, such as the scalp, eyelid margins, nasolabial folds, ears, and upper trunk. The primary underlying cause is believed to be an inflammatory reaction to Malassezia species (formerly Pityrosporum species), a yeast form present on human skin. This organism acts as a cofactor linked to T-cell depression, elevated sebum levels, and activation of the alternative complement pathway. Seborrhea is especially prevalent in immunocompromised patients, older adults, and individuals with Parkinson’s disease.
Clinical Concept: In young children, cradle cap is a common form of seborrhea, while the diaper area is usually spared.
Lesions typically present in oily, hair-bearing regions of the head, neck, and chest. Clinical features include:
Diagnosis: Made clinically based on the characteristic distribution of lesions and a history of a waxing and waning course. Laboratory testing is generally not required, though fungal cultures can be performed to rule out tinea capitis in pediatric patients.
Management focuses on topical antifungals, anti-inflammatory agents, and keratolytics during flares:
| Therapy Class | Agents / Options | Clinical Considerations |
|---|---|---|
| Topical Antifungals | Ketoconazole, Selenium sulfide shampoo | First-line treatment supporting the fungal etiology hypothesis. |
| Topical Steroids | Class IV or lower corticosteroid creams, lotions, or solutions | Helpful during flares. High-potency topical steroids are discouraged due to risks of subcutaneous atrophy and telangiectasia. |
| Topical Immunomodulators | Pimecrolimus, Tacrolimus | Non-steroidal anti-inflammatory options for acute flares. |
| Other Topicals & Keratolytics | Coal tar shampoo, Sulfur or sulfonamide combinations, Propylene glycol | Coal tar functions as a keratolytic; petroleum jelly can help soften and remove stubborn lesions prior to applying medicated shampoos. |
| Systemic Antifungals | Oral Ketoconazole, Fluconazole | Reserved for severe or treatment-refractory seborrheic dermatitis. |
Treatment Pitfalls to Avoid:
1. Barankin B, Anatoli F. Derm Notes: Clinical Dermatology Pocket Guide. Philadelphia, PA: F.A. Davis; 2006.
2. Schmidt JA. Seborrheic dermatitis: a clinical practice snapshot. Nurse Pract. 2011;36(8):32–37.
3. Selden ST. Seborrheic dermatitis. Medscape.
