A 34-year-old man with a 10-year history of a chronic skin condition is referred for evaluation and treatment. Over the years, he has been treated with several regimens such as topical steroids and oral retinoids without adequate control. Most of the lesions are asymptomatic, although some can be pruritic. Physical examination reveals scattered plaques with scale on his hands; pitting of his nails is also apparent.
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Psoriasis is a chronic inflammatory papulosquamous disorder that affects over 3% of the US population, or 7.4 million Americans, aged 20 years and older.1 The predominant form of psoriasis is the plaque variant, which is characterized by erythematous plaques most frequently appearing on the knees, elbows, and scalp.
Once considered a disease of the skin and joints, psoriasis is now associated with multiple comorbidities including cardiometabolic diseases and mood disorders such as depression.2,3 The disease is driven by an interplay between the immune system, psoriasis-associated susceptibility loci, autoantigens, and environmental factors.4
Over the past 2 decades, much has been learned about the pathogenesis of this disease allowing for targeted treatments. Psoriasis is now recognized as a T-cell mediated disease that result in elevated levels of tumor necrosis factor (TNF), interleukin (IL)-17, and IL-23.4 The aberrant immune response is expressed in genetically predisposed individuals following exposure to specific autoantigens.
Topical therapies for psoriasis including corticosteroids, vitamin D analogues, and retinoids are generally used in the management of mild psoriasis.5 These topical treatments are impractical for management of widespread disease and are ineffective for psoriatic arthritis.
For patients with moderate to severe psoriasis, ultraviolet light therapy may induce remission of skin lesions.5 Oral systemic therapies include acitretin, cyclosporine, and methotrexate; the latter 2 agents also are effective for psoriatic arthritis. All systemic therapies require laboratory monitory.5
Biologic agents have revolutionized the management of moderate to severe psoriasis and afford control of disease by blocking TNF, IL-17, or IL-23.5 Many biologic agents are available and a recent meta-analysis by Armstrong et al concluded that the IL-17 inhibitors brodalumab and ixekizumab and the IL-23 inhibitors guselkumab and risankizumab-rzaa are associated with the greatest short-term and long-term response rates.
At weeks 44 to 60, the treatments with the highest response rates were risankizumab-rzaa (79.4%; 95% CI, 75.5%-82.9%), guselkumab (76.5%; 95% CI, 72.1%-80.5%), brodalumab (74.0%; 95% CI, 69.3%-78.1%), and ixekizumab (73.9%; 95% CI, 69.9%-77.5%).7 Additionally, the oral phosphodiesterase (PDE4) inhibitor apremilast is approved to treat severe plaque psoriasis and active psoriatic arthritis.8
Stephen Schleicher, MD, is director of the DermDox Center for Dermatology in Pennsylvania, as well as an associate professor of medicine at Commonwealth Medical College and a clinical instructor of dermatology at Arcadia University and Kings College.
1. Rachakonda TD, Schupp CW, Armstrong AW. Psoriasis prevalence among adults in the United States. J Am Acad Dermatol. 2014;70(3):512-516. doi:10.1016/j.jaad.2013.11.013
2. Ryan C, Kirby B. Psoriasis is a systemic disease with multiple cardiovascular and metabolic comorbidities. Dermatol Clin. 2015;33(1):41-55. doi:10.1016/j.det.2014.09.004
3. Takeshita J, Grewal S, Langan SM, et al. Psoriasis and comorbid diseases: epidemiology. J Am Acad Dermatol. 2017;76(3):377-390. doi:10.1016/j.jaad.2016.07.064
4. Hawkes JE, Chan TC, Krueger JG. Psoriasis pathogenesis and the development of novel targeted immune therapies. J Allergy Clin Immunol. 2017;140(3):645-653. doi:10.1016/j.jaci.2017.07.004
5. Golbari NM, Porter ML, Kimball AB. Current guidelines for psoriasis treatment: a work in progress. Cutis. 2018;101(3S):10-12.
6. Singh JA, Guyatt G, Ogdie A, et al. Special Article: 2018 American College of Rheumatology/National Psoriasis Foundation guideline for the treatment of psoriatic arthritis. Arthritis Care Res (Hoboken). 2019;71(1):2-29. doi: 10.1002/acr.23789
7. Armstrong AW, Puig L, Joshi A, et al. Comparison of biologics and oral treatments for plaque psoriasis: a meta-analysis. JAMA Dermatol. 2020;156(3):258-269. doi:10.1001/jamadermatol.2019.4029
8. Otezla. Package insert. Amgen; 2020. Accessed March 3, 2021. https://www.pi.amgen.com/~/media/amgen/repositorysites/pi-amgen-com/otezla/otezla_pi_english.ashx