Treatment of Inverse/Intertriginous Psoriasis: Updated Guidelines from the Medical Board of the National Psoriasis Foundation

August 2017 | Volume 16 | Issue 8 | Original Article | 760 | Copyright © August 2017


Hasan Khosravi MD,a Michael P. Siegel PhD,b Abby S. Van Voorhees MD,c and Joseph F. Merola MD MMSca,d

aHarvard Medical School, Boston, MA bNational Psoriasis Foundation, Portland, OR cEastern Virginia Medical School, Norfolk, VA dBrigham and Women’s Hospital, Boston, MA

METHODOLOGY

The literature was reviewed for new reports on inverse psoriasis since the last National Psoriasis Foundation consensus by HK.10 Articles were obtained from Medline using the following MeSH terms: “psoriasis and skin diseases,” “genital diseases, male or female,” “anus diseases,” “buttocks,” “inverse,” “flexural,” and “intertriginous.” 14,054 total articles resulted from this search, and 34 articles were reviewed. Articles were chosen based on documentation of new treatments, modifications or improvements to current management, and/or further trials conducted on current medications for inverse psoriasis. Evidence levels were graded according to guidelines by Shekelle P.G., et al.11 IA includes evidence from meta-analyses of randomized controlled trials; IB includes randomized controlled trials; IIA includes controlled studies without randomization; IIB includes quasiexperimental study; III includes non-experimental descriptive studies such as comparative studies, correlation studies, and case-control studies; and level IV includes expert committee reports or clinical experience of respected authorities. Importantly, the amount of literature was limited, and study quality varied widely.

Evidence

1. The short-term therapy for inverse psoriasis continues to be low to mid-potency topical steroids (Table 1). 2. The recommended long term therapy is preferably tacrolimus or pimecrolimus over calcitriol or calcipotriene (calcipotriol) as listed in Table 2. Based on a study by Ortonne et al, calcitriol is suggested over calcipotriene for exural psoriasis treatment.14 3. Based on anecdotal evidence and case reports listed in Table 4, the use of antimicrobial agents is considered second-line therapy. Antimicrobial therapy can include topical imidazoles; based on clinical experience, antiprotozoal agents such as iodoquinol and combinations with topical steroids have also proven effective in inverse psoriasis. 4. Other recommended second line therapies includes emollients and tar-based products. One case report demonstrated improvement of intertriginous psoriasis with coal tar 2% foam.28 This is thought to be due to the suppression of keratinocyte differentiation along with anti-inflammatory effects.28 The use of these agents combined with a low-potency topical steroid may be effective for inverse psoriasis. 5. Treatment modalities that can be used in inverse psoriasis resistant to topical therapy include excimer therapy.29 As listed in Table 5, case reports have documented improvement in intertriginous psoriasis after therapy with excimer light and tacrolimus.29 Unfortunately, few studies have evaluated the safety of excimer therapy with drawbacks including the cost and limited availability.30 6. Studies listed in Table 6 have evaluated treatment with botulinum toxin type-A. Potential mechanisms include a reduction in perspiration and inhibition of proalgogenic substance release.31 7. Other systemic treatments should be strongly considered in inverse psoriasis that is resistant to conventional therapy, involves a large surface area, and/or has a high impact on quality of life based on patient report. Such treatments include methotrexate, anti-TNF inhibitors, anti-IL12/IL23 in- hibitors, oral PDE4 inhibitors, and newer anti-IL17 therapy; of the biologic therapies, adalimumab and ustekinumab have shown to be effective in case reports as listed in Table 7. However, etanercept, in iximab, adalimumab, ustekinumab, secukinumab, ixekizumab, and apremilast have been approved for psoriasis therapy and can be considered in inverse psoriasis resistant to topical therapy.33 With respect to these agents, the consensus committee has noted a strong response based on clinical experience.Figure 1