Table of Content


Spring 2016, Vol. 24 No. 1

Hong Kong J. Dermatol. Venereol. (2016) 24, 46-48

Reports on Scientific Meetings

Dinner Symposium on Seborrhoeic Dermatitis

Reported by BTH Chan 陳子浩 and CK Wong 黃之鍵

Date:   15 January 2016
Venue:   Sheraton Hong Kong Hotel & Towers, Tsimshatsui, Kowloon, Hong Kong
Organiser:   The Hong Kong Society of Dermatology & Venereology

Differential diagnoses of adult seborrheic dermatitis and infantile seborrheic dermatitis

Speaker: Johnny Chun-yin Chan
Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong

The differential diagnoses of seborrhoeic dermatitis are many and varied. The onset, clinical course, symptoms and distribution of the skin lesions often provide hints to the underlying diagnosis. Regular monitoring of the treatment response and reviewing the diagnosis accordingly is advised. The differential diagnoses of adult seborrhoeic dermatitis on the face include atopic dermatitis, contact dermatitis (allergic/irritant), perioral dermatitis, psoriasis, rosacea, connective tissue disease (systemic lupus erythematosus, dermatomyositis and cutaneous adverse effects due to target therapy. On the scalp, the differential diagnoses are psoriasis, dermatitis (atopic/contact), infection (tinea capitis, scabies) and dermatomyositis. On the upper chest, psoriasis, dermatitis (atopic/contact), infection (tinea corporis, pityriasis versicolour) and Darier disease have to be considered. The differential diagnoses of infantile seborrhoeic dermatitis are atopic dermatitis, pityriasis alba, napkin dermatitis (allergic/irritant), cutaneous infection (tinea capitis, impetigo, candidiasis) and Langerhans cell histiocytosis.

Learning points:
Serious medical conditions can mimic recalcitrant SD.

Understanding seborrhoeic dermatitis pathogenesis

Speaker: Giuseppe Micali
Department of Dermatology, University of Catania, Italy

The pathogenesis of seborrhoeic dermatitis (SD) is still unclear but it seems to be multifactorial. Malassezia spp., a lipophilic yeast, has been implicated as a cause of SD. M. globosa and M. restricta are considered to be the predominant species found in patients with SD. The interaction of Malassezia spp. with sebaceous lipids leads to the release of unsaturated fatty acids on the skin surface. This induces the production of proinflammatory cytokines, which can elicit an inflammatory skin response in reactive individuals. This theory is supported by the therapeutic efficacy of antifungal agents in the treatment of SD. Patients with SD are much more commonly affected by hyperseborrhoea. Cholesterol and its ester are increased in the sebum of patients with SD. Squalene is reduced whereas squalene peroxide is increased. As a result, the synthesis and release of proinflammatory cytokines by keratinocytes are increased. Other precipitating factors of SD include drugs (lithium, haloperidol, chlorpromazine, methyldopa, cimetidine), nutritional deficiency (zinc), neurological degenerative disorders (Parkinson's disease, facial palsy), immune suppression (AIDS), environmental factors (excessive sun exposure) and lifestyle factors (alcohol consumption).

Learning points:
The pathogenesis of seborrhoeic dermatitis is multifactorial, including Malassezia spp., hyperseborrhoea, immune suppression, drugs, neurological disorders, nutrition deficiency, environmental and lifestyle factors.

Unmet needs in seborrhoeic dermatitis treatment and practical management: an Asian consensus guide

Speaker: Wai-kwong Cheong
Specialist Skin Clinic and Associates, Singapore

Current topical treatments for seborrhoeic dermatitis include corticosteroids, antifungals, calcineurin inhibitors. Both topical steroids and calcineurin inhibitors act through their anti-inflammatory effect. Long term use of topical steroids is limited by their side-effects and relapse on discontinuation is common. Limitations of topical calcinuerin inhibitors include high cost and off-label use. Though there are few side-effects on prolonged use, topical antifungals have limited anti-inflammatory properties and their action is slower when compared to topical steroids. Sebclair®, a non-steroidal agent, has demonstrated anti-inflammatory and antifungal properties, and can be used regardless of age, duration of use and the sites of the affected areas. It has also demonstrated good tolerability. In one clinical study, it was shown to have an efficacy comparable to desonide 0.05% cream with fewer relapses. In view of the chronic relapsing nature of seborrhoeic dermatitis, treatments should be safe when used on a long term basis with fewer relapses on discontinuation. As a result, first-line treatment and maintenance treatment with non-steroidal alternatives such as Sebclair® or antifungals have been proposed for treating mild to moderate seborrhoeic dermatitis. Its use in combination with topical steroids is recommended for moderate to severe cases or cases not responding to non-steroidal agents alone.

Learning points:
Use of non-steroidal agents with or without topical steroids can be considered in the long term treatment of seborrhoeic dermatitis.

Evidence based medicine - Sebclair®

Speaker: Giuseppe Micali
Department of Dermatology, University of Catania, Italy

The treatment of seborrhoeic dermatitis mainly targets inflammation, sebum excretion and proliferation of Malassezia spp. First-line treatments for seborrhoeic dermatitis include topical corticosteroids and antifungals. Potential side effects, intolerability and unfavourable cosmetic acceptability may lead to poor long-term compliance of treatment. Topical calcineurin inhibitors could be used off-label to treat the condition. Currently, non-steroidal topical agents with anti-inflammatory and antifungal activity such as Sebclair® or Promiseb® are available. Several in vitro and in vivo studies on the efficacy of these non-steroidal topical agents in treating mild to moderate seborrhoeic dermatitis have been performed. In a study on the efficacy of Sebclair® cream on mild to moderate seborrhoeic dermatitis, significant improvement in desquamation, erythema and pruritus over the face was recorded and a complete response was found in half of the cases with good tolerance after four weeks of treatment. Another study showed that both 1% ketoconazole shampoo and Sebclair® shampoo can lead to significant reduction of scaling and pruritus over the scalp with good tolerance after eight weeks of treatment.

Learning points:
Studies showed that Sebclair® cream and shampoo are effective against mild to moderate seborrhoeic dermatitis.