Recalcitrant hand pompholyx: variable response to etanercept

Management of chronic hand and foot eczema. An Australia/New Zealand Clinical narrative

Chronic hand/foot eczemas are common, but treatment is often challenging, with widespread dissatisfaction over current available options. Detailed history is important, particularly with regard to potential exposure to irritants and allergens. Patch testing should be regarded as a standard investigation. Individual treatment outcomes and targets, including systemic therapy, should be discussed early with patients, restoring function being the primary goal, with clearing the skin a secondary outcome. Each new treatment, where appropriate, should be considered additive or overlapping to any previous therapy. Management extends beyond mere pharmacological or physical treatment, and requires an encompassing approach including removal or avoidance of causative factors, behavioural changes and social support. To date, there is little evidence to guide sequences or combinations of therapies. Moderately symptomatic patients (e.g. DLQI ≥ 10) should be started on a potent/super-potent topical corticosteroid applied once or twice per day for 4 weeks, with tapering to twice weekly application. If response is inadequate, consider phototherapy, and then a 12-week trial of a retinoid (alitretinoin or acitretin). Second line systemic treatments include methotrexate, ciclosporin and azathioprine. For patients presenting with severe symptomatic disease (DLQI ≥ 15), consider predniso(lo)ne 0.5-1.0 mg/kg/day (or ciclosporin 3 - 5 mg/kg/day) for 4-6 weeks with tapering, and then treating as for moderate disease as above. In non-responders, botulinum toxin and/or iontophoresis, if associated with hyperhidrosis, may sometimes help. Some patients only respond to long-term systemic corticosteroids. The data on sequencing of newer agents, such as dupilumab or JAK inhibitors, are immature.

The key role of aquaporin 3 and aquaporin 10 in the pathogenesis of pompholyx

Pompholyx remains a chronic skin affliction without a compelling pathophysiological explanation. The disease is characterized by the sudden onset of vesicles exclusively in the palms and soles which generally resolves. However, the disease may progress and the vesicles may expand and fuse; with chronicity there is deep fissuring. Multiple therapeutic approaches are available, but the disease is often resistant to conventional treatments. Currently, oral alitretinoin is used for patients with resistant chronic disease; however, this therapy is only approved for use in the UK, Europe and Canada. In this paper we wish to put forward a hypothesis: exposure to water and the subsequent steep osmotic gradient imbalance are key factors driving skin dehydration seen in pompholyx patients once the disease becomes chronic. The mechanistic explanation for the epidermal fissuring might lie in the over-expression across the mid and upper epidermis, including the stratum corneum, of two water/glycerol channel proteins aquaporin 3 and aquaporin 10, expressed in the keratinocytes of afflicted pompholyx patients. The over-expression of these two aquaporins may bridge the abundantly hydrated dermis and basal epidermis to the outer environment allowing cutaneous water and glycerol to flow outward. The beneficial effects reported in alitretinoin-treated patients with chronic hand eczemas may be due potential regulation of aquaporin 3 and aquaporin 10 by alitretinoin.

[Management of chronic hand eczema]

The management of hand eczema, more readily called chronic hand dermatitis, is complex. This heaviness is related not only to the disease itself by its different clinical forms but also the multiplicity and diversity of etiological factors, triggering / maintaining or aggravating factors. The repeated therapeutic failures are ransom of incorrect information about the disease and its environment, a lack of clarity in the prescription and duration of treatment in general too short. The reference treatment is high potency topical steroids with or without occlusion for 4-8 weeks followed by alitretinoin 30 mg / day for at least 3-6 months with a monthly lipid and liver monitoring and mandatory monthly pregnancy test in women of childbearing. Associated measures and patient education are the cornerstones of successful treatment. Other alternative treatments such as phototherapy, methotrexate, cyclosporin, mycophenolate mofetil etc. can be considered in case of resistance or for clearing followed by topical treatments.

Pompholyx: a review of clinical features, differential diagnosis, and management

Pompholyx is a vesicobullous disorder of the palms and soles. The condition is hard to treat because of the peculiarities of the affected skin, namely the thick horny layer and richness of the sweat glands. In this article, we review the available therapies, and score the treatments according to the level of evidence. The cornerstones of topical therapy are corticosteroids, although calcineurin inhibitors also seem to be effective. Topical photochemotherapy with methoxsalen (8-methoxypsoralen) is as effective as systemic photochemotherapy or high-dose UVA-1 irradiation. Systemic therapy is often necessary in bullous pompholyx. Corticosteroids are commonly used although no controlled study has been published to date. For recalcitrant cases, corticosteroids are combined with immunosuppressants. Alitretinoin has efficacy in chronic hand dermatitis including pompholyx. Another evolving treatment seems to be the intradermal injection of botulinum toxin. Radiotherapy might be an option for selected patients not responding to conventional treatment. In practice, patients benefit most from a combination of treatments.

Innovative management of severe hand dermatitis

The successful treatment of hand dermatitis (HD) depends less on the selection of the proper topical steroid or a particular systemic agent than on addressing any underlying cause or perpetuating factor. Thus, innovative treatment is based on comprehensively addressing the patient's problem. Aggressive approaches may be required for the most severe forms of HD.