Medication Summary
The goals of pharmacotherapy are to reduce morbidity and to prevent complications. Due to the rarity of this disease, therapy has been based on anecdotal reports. [37] No large controlled trials have been performed.
A study of 12 patients by Dickens revealed that 80% of the patients had improvement from the use of oral retinoids. Clinical improvement can be expected within 4-6 months. [38]
The use of monoclonal antibodies that suppress the immune system may improve the clinical aspects of the disease. [39] A case series has compared infliximab with etanercept and found a more rapid onset of action with infliximab but roughly equal treatment duration required when compared with etanercept. [40] Adalimumab has been added to the list, [41] as has ustekinumab. [42, 43] Infliximab has been reported anecdotally to be of benefit, as has etanercept and ustekinemab. [42, 44, 45, 46, 47, 48]
Immunosuppressants inhibit cell growth and proliferation. They may also cause immunosuppression. [49] Immunosuppressants inhibit key factors that regulate the immune system. Case reports have shown benefit in some patients with pityriasis rubra pilaris. [50, 51]
Results from a small open-label, single-arm, 24-week clinical trial showed that ixekizumab, an interleukin 17A inhibitor, was safe and effective for treating pityriasis rubra pilaris. [52] Seven of 11 subjects saw at least 50% improvement and four saw long-term remission.
Retinoids
Class Summary
These agents decrease the cohesiveness of abnormal hyperproliferative keratinocytes. They modulate keratinocyte differentiation.
Acitretin (Soriatane)
Acitretin is a metabolite of etretinate and related to both retinoic acid and retinol (vitamin A). Its mechanism of action is unknown. However, it is thought to exert therapeutic effects by modulating keratinocyte differentiation, keratinocyte hyperproliferation, and tissue infiltration by inflammatory cells. It is approved for the treatment of severe psoriasis.
Isotretinoin (Amnesteem, Claravis, Sotret)
Isotretinoin is a synthetic 13-cis isomer of the naturally occurring tretinoin (trans-retinoic acid). It is approved for use in severe recalcitrant nodular acne. A review by Allison et al revealed clearing in 5 of 6 pediatric patients with pityriasis rubra pilaris within 6 months.
A US Food and Drug Administration–mandated registry is now in place for all individuals prescribing, dispensing, or taking isotretinoin. For more information on this registry, see iPLEDGE. This registry aims to further decrease the risk of pregnancy and other unwanted and potentially dangerous adverse effects during a course of isotretinoin therapy.
Immunosuppressants
Class Summary
These agents inhibit cell growth and proliferation. They may also cause immunosuppression. Immunosuppressants inhibit key factors that regulate the immune system.
Cyclosporine (Neoral, Sandimmune)
Cyclosporine is a cyclic polypeptide immunosuppressant agent produced as a metabolite by the fungus species Beauvaria nivea. It is approved for use in organ transplantation patients, rheumatoid arthritis, and psoriasis.
Azathioprine (Azasan, Imuran)
Azathioprine antagonizes purine metabolism and inhibits the synthesis of DNA, RNA, and proteins. It may decrease the proliferation of immune cells, which results in immunosuppression. It is approved for use in transplantation patients and patients with rheumatoid arthritis.
Methotrexate (Rheumatrex)
Methotrexate is an antimetabolite that inhibits dihydrofolate reductase, thereby hindering DNA synthesis and cell reproduction. Successful treatment is reported. Follow the same guidelines as for use in psoriasis. Improvement may occur in 6 weeks, with a complete response after 3-4 months. Relapse may occur upon discontinuation.
DMARDs, TNF Inhibitors
Class Summary
The use of monoclonal antibodies that suppress the immune system may improve the clinical aspects of the disease.
Etanercept (Enbrel)
Etanercept is a soluble p75 TNF receptor fusion protein (sTNFR-Ig). It inhibits TNF binding to cell surface receptors, which, in turn, decreases inflammatory and immune responses.
Vitamins
Class Summary
Agents like vitamin A have been reported to improve the clinical aspects of the disease.
Vitamin A
Improvement with vitamin A therapy has been reported; however, synthetic retinoids are more effective.
Monoclonal Antibodies
Class Summary
Monoclonal antibodies are genetically engineered chimeric murine-human immunoglobulins directed against tumor necrosis factor, which in turn interferes with cytokine driven inflammatory processes.
Infliximab (Remicade)
Infliximab is a chimeric monoclonal antibody that binds specifically to human tumor necrosis factor-alpha. It is approved for the treatment of rheumatoid arthritis, Crohn disease, ankylosing spondylitis, and psoriatic arthritis. Several reported cases describe adult-onset pityriasis rubra pilaris with excellent responses to infliximab.
Adalimumab (Humira)
Adalimumab is a recombinant human IgG1 monoclonal antibody specific for human TNF. It binds specifically to TNF-alpha and blocks interaction with p55 and p75 cell-surface TNF receptors. This interferes with cytokine-driven inflammatory processes. It also lyses surface TNF-expressing cells in vitro in the presence of complement, but it does not bind to TNF-beta (lymphotoxin).
Ustekinumab (Stelara)
Ustekinumab is a human monoclonal antibody directed against IL-12 and IL-23, thereby interfering with T-cell differentiation and activation and subsequent cytokine cascades.
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Reddish orange plaques on the trunk.
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Follicular hyperkeratosis seen on the dorsal aspect of the proximal phalanges.
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Plantar keratoderma with an orange hue on the soles.
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Palmar keratoderma with an orange hue on the palms.