PubMed: Published on April 2022

Seborrheic dermatitis (SD) is a common inflammatory skin disease, which is particularly prevalent in older adults, presenting with papulosquamous morphology in areas rich in sebaceous glands, particularly the scalp, face, and body folds.

Pathogenesis

While a specific cause of seborrheic dermatitis remains largely unelucidated, the currently understood pathogenesis of seborrheic dermatitis revolves around the presence of Malassezia yeast colonies and an inflammatory response in the affected individual.

Sebaceous glands may play a permissive role in the pathogenesis of seborrheic dermatitis, possibly by creating a favorable milieu for the growth of fungi of the genus Malassezia. 

The inflammation of seborrheic dermatitis may be mediated by the innate immune system response to irritants produced by Malassezia, including free fatty acids, lipase, and reactive oxygen species.

Keratinocyte proliferation resulting from inflammasome response in the host skin leads to the clinically relevant symptoms of seborrheic dermatitis.

Treatment Options

There are multiple treatment options based on individual patient situations and preferences. The approach will vary according to individual patient situations, preferences the patient’s age and the distribution and severity of the condition.

It is essential to discuss good general skincare practices, including the use of a soap-substitute and appropriate moisturizing.

Treatments should address the underlying disease process and any secondary features, especially the hyperkeratotic scale, Staphylococcal infection, and associated symptoms, particularly pruritus.

Topical treatment

Topical treatment is the gold standard, but oral therapy may be required in certain cases. A typical formulary should include antifungals, keratolytics, antipruritics, and anti-inflammatories (topical corticosteroids and calcineurin inhibitors). Moreover, treatment rotation may be more effective and associated with fewer adverse reactions than persisting with monotherapy. 

For scalp and non-scalp SD treatment, evidence supports the use of topical 2% ketoconazole, 1% ciclopirox, 1% zinc pyrithione, and 1% hydrocortisone. 

Intermittent use of a mild topical corticosteroid and imidazole antifungal combination is convenient and can be very effective, but a potent corticosteroid may be necessary for short term treatment of scalp ASD. 

In order to maximize effectiveness and minimize adverse pharmacologic effects, effective treatment for older adults must take into account changes in lifestyle and metabolism that occur with aging.