Clinical Reference / Therapeutic Strategies / Seborrheic Dermatitis

Seborrheic Dermatitis


Key Points

  • Seborrheic dermatitis is a chronic intermittent rash typically affecting the face, ears, scalp, and trunk.
  • It is marked by an erythematous papular or macular eruption often with greasy yellow scale, sometimes accompanied by pruritus.
  • This condition is believed to result from seborrhea and from an inflammatory response to the commensal skin organism, Malassezia fungi.
  • Thus, the mainstay of treatment includes topical anti-fungal agents alone or in combination with topical steroids.
  • Seborrheic dermatitis can be severe in immunocompromised individuals or persons with neurologic disease.

Clinical overview

Seborrheic dermatitis is a chronic intermittent rash affecting areas rich in sebaceous glands, and is marked by an erythematous papular or macular eruption often with greasy yellow scale, sometimes accompanied by pruritus. It can be limited to the scalp (a.k.a. dandruff), but it also can involve the face, the external auditory canal, any hairy or intertriginous area such as the chest or genitalia, and in rare cases can progress to a generalized erythroderma. On the face, it classically affects the nasolabial folds, eyebrows, glabella, and beard area; blepharoconjunctivitis may also occur. The mainstay of treatment includes anti-fungal agents alone or in combination with topical steroids.

Seborrheic dermatitis can be severe in patients with HIV (especially in persons with CD4 count below 400) and persons with neurologic disease. It may be exacerbated by stress, and patients sometimes report improvement with sun exposure. Seborrheic dermatitis frequently coexists or is overlapping with other skin diseases such as rosacea or psoriasis (sebopsoriasis).

In children, seborrheic dermatitis can present as “cradle cap” (frontal and parietal scalp regions and/or external auditory canal involvement only) or in conjunction with similar eruptions on the face, neck, chest and diaper area. On the face, the nasolabial folds, medial cheeks, glabella, eyebrows, and forehead are typical affected areas – similar to disease seen in adults.

Initial Evaluation

Erythematous, scaly, oily-looking patches on the face (nasolabial folds, medial cheeks, chin, glabella, forehead) and thick crust on the scalp are typical affected areas.

Seborrheic dermatitis can also present as erythematous papules without scale. The distribution of affected areas on the face (nasolabial folds, medial cheeks, chin, and glabella and forehead) and chest are suggestive of the diagnosis.

Seborrheic dermatitis in the setting of advanced HIV disease (note temporal wasting as another cutaneous manifestation of AIDS).

Prevalence

The disease in adults is believed to be more common than psoriasis, affecting at 2-5% of the population. Males are affected more often than females.

Natural history

The disease usually starts with dandruff, which may gradually progress through erythema and increasing scaling of the scalp. The disease lasts for years to decades with periods of improvement in warmer seasons and periods of exacerbation in the colder months. Patients typically describe improvement with sun exposure. Widespread lesions may occur as a result of improper topical treatment.

Pathogenesis

The three possible etiologic factors are the yeasts (Malassezia fungi/ Pityrosporum ovale), sebaceous secretions and individual sensitivity, but the exact interrelationship between them is still a matter of controversy.

Principles of Seborrheic Dermatitis Management

  • Seborrheic dermatitis is a chronic intermittent condition. There is an initial treatment period followed by maintenance therapy. Many patients will relapse if maintenance therapy is not adequate.
  • Topical antifungals are the mainstay of the treatment of seborrheic dermatitis.

First-line treatment: Topical ketoconazole 2% shampoo such as Nizoral (scalp), cream or gel such as Xolegel (face).

Topical antifungal agents are first-line treatment of seborrheic dermatitis. Severe cases will require addition of a topical steroid or other anti-inflammatory.

Scalp

For mild disease of the scalp

Use shampoos with activity against Malassezia are used daily:

  • Ketoconazole shampoo 2% (prescription) or 1% (OTC) twice weekly
  • Use an alternative shampoo, such as zinc pyrithione shampoo (such as Head & Shoulders) or selenium sulfide shampoo (such as Selsun or Selsun Blue) or ciclopirox (such as Loprox) on the other days
  • In very young infants who require treatment, consider using bifonazole shampoo, 3 to 5% salicylic acid in olive oil or a water-soluble base, or low-potency corticosteroids (e.g., 1% hydrocortisone) in a cream or lotion for few days.
  • This is an effective strategy and often significantly reduces the need for topical steroids.
  • Instructions to the patient: Shampoo is applied to wet hair, worked up into a lather for 5-10 minutes, then rinsed. Any conditioner or cream rinse may follow.

For moderate-to-severe disease of the scalp

Prescribe a low or mid-potency corticosteroid-containing lotion:

  • Triamcinolone acetonide 0.1% lotion (such as Kenalog).
  • Fluocinonide 0.05% lotion (such as Lidex or Vanos).
  • For best results, the solution should be streaked in three parallel rows (about 4-5 drops in each row) onto dry skin, and massaged into the scalp.

A fluocinolone-containing oil (such as Dermasmoothe FS scalp oil) may be indicated for patients with dry scalp or dry hair.

For severe disease of the scalp

Refer patients to the dermatologist.

Face & body

For mild disease of the face and body

  • Topical antifungal agents such as ketoconazole 2% cream or gel applied b.i.d. are first-line.
  • For ears, consider a low-potency corticosteroid lotion.
  • For eyelashes, use baby shampoo on a cotton ball to gently remove scale.
  • For more severe cases, add a topical steroid.
  • Seborrheic dermatitis of non-scalp regions is extremely steroid-responsive, and therefore potent fluorinated steroids need not be used.
  • Since the face and body folds are often involved, prescribe a non-fluorinated (non-atrophogenic) steroid: e.g., desonide 0.05% (such as Desonate, Desowen, LoKara, or Verdeso), aclometasone dipropionate cream 0.05% (such as Aclovate), or hydrocortisone 1% or 2.5% cream) to be applied twice daily.
  • Topical steroids may be used alone or in conjunction with topical antifungal creams.

For severe or non-responsive disease

Recommend referral of patients to the dermatologist.

Treatment Summary for Seborrheic Dermatitis (all topical)

First-line Adjunct treatment Alternative treatment Maintenance therapy
Face ketoconazole gel, cream corticosteroids sulfacetamide/sulfur calcineurin inhibitors or metronidazole ketoconazole (1-2x per week)
Scalp ketoconazole shampoo corticosteroids, tar or salicylic acid shampoo ketoconazole, zinc pyrithione, selenium sulfide shampoo (1-2x per week)
Body ketoconazole shampoo, cream, gel corticosteroids metronidazole ketoconazole, zinc pyrithione, selenium sulfide shampoo (1-2x per week)

Pitfalls

  • In recalcitrant cases rule out psoriasis or tinea capitis. Seborrheic dermatitis after infancy and before adolescence is rare (owing to inactivity of sebaceous glands). In contrast, tinea capitis is common in this age group. The presence of various degrees of hair loss is suggestive of tinea capitis. A fungal culture and/or scraping should be taken to exclude tinea in this age group before using corticosteroids on the scalp.
  • HIV/AIDS should be considered as a pre-existing condition in patients with severe seborrheic dermatitis and HIV risk factors.
  • In addition to the coexisting conditions described above, a seborrheic dermatitis-like picture can be the presenting feature of all forms of Langerhans’ cell histiocytoses and other rare inherited or congenital disorders (e.g., Hailey-Hailey disease, primary immunodeficiencies).
  • Seborrheic dermatitis tends to recur and relapse repeatedly; therefore, therapy with medicated shampoos (and often intermittent topical steroids as well) may need to be continued indefinitely. Note that these shampoos can be irritating to the skin, although ketoconazole shampoo is less irritating than selenium sulfide preparations.

Situations requiring dermatologic consultation

  • Non-responsive or severe disease
  • When the diagnosis of seborrheic dermatitis is not clear
  • Severe seborrheic dermatitis in the setting of advanced neurologic or HIV disease

Clinical Cases

Case 1

Mild seborrheic dermatitis (face only)

  • 65-year-old man
  • long-standing erythema with overlying greasy scale on the nasolabial folds, melolabial folds, glabella, and chin
  • Improves with sun exposure

Initial treatment

  • Ketoconazole 2% cream b.i.d.
  • Ketoconazole 2% shampoo every other day (10 minutes lather)
  • Follow-up at 6 weeks

Follow-up evaluation

  • Ketoconazole 2% cream twice weekly
  • Ketoconazole 2% shampoo twice weekly

Case 2

Severe seborrheic dermatitis (face, scalp, and chest)

  • 32-year-old man
  • erythema and scaling of the scalp, ears, central face, and chest
  • slight improvement with topical ketoconazole 2% cream

Initial treatment

  • Ketoconazole 2% cream b.i.d. (face/ears)
  • Desonide 0.05% cream b.i.d. (face/ ears)
  • Ketoconazole 2% shampoo every day (10 minutes lather, including ears & chest) for 2 weeks
  • Triamcinolone 0.1% scalp solution every day (can also be used on chest)
  • Follow-up at 4-6 weeks

Follow-up evaluation

  • Ketoconazole 2% cream twice weekly (face)
  • Ketoconazole 2% shampoo three times weekly (scalp/ears/chest)

Suggested Reading

Naldi L, Rebora A. Clinical practice: seborrheic dermatitis. NEJM. 2009;360:387-396.