A 29-year-old man presents to the dermatology clinic for evaluation of a rash on his body that began 2 weeks ago. The eruption is asymptomatic and involves his back and chest. He denies fever, malaise, recent sore throat, or enlarged lymph glands. He drinks in moderation and does not smoke. He denies a history of systemic disease or illicit drug use. Examination reveals multiple erythematous scaly patches located on his trunk. No nail, oral, or genital abnormalities are detected and his palms and soles are uninvolved.
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Guttate psoriasis is an acute form of psoriasis characterized by the sudden onset of drop-like (guttate) papules and patches covered with a fine scale. The rash is usually located on the trunk and, to a lesser degree, the extremities. The condition may arise in association with streptococcal pharyngitis (Streptococcus pyogenes)1 or, less frequently, a perianal streptococcal infection.2 At least 1 case report has linked the onset of guttate psoriasis with a positive SARS-CoV-2 blood test, confirming COVID-19 infection.3
Guttate psoriasis is most commonly seen in children, adolescents, and adults younger than 30 years of age, and usually arises 1 to 3 weeks after infection.4 The condition may resolve spontaneously weeks to months after initial presentation. Topical steroids are the mainstay of therapy for mild psoriasis and UV-B light therapy is the mainstay for moderate to severe disease.4
Because of the link to streptococcal infection, clinicians often institute a course of antibiotics at disease onset. A recent Cochrane review, however, found insufficient evidence to validate the effectiveness of this therapy. The review authors recommended further trials to assess the efficacy and tolerance of penicillin V potassium or amoxicillin in children and young adults with guttate psoriasis.5
Stephen Schleicher, MD, is director of the DermDox Center for Dermatology in Pennsylvania, associate professor of medicine at Commonwealth Medical College, and clinical instructor of dermatology at Arcadia University and Kings College.
1. Telfer NR, Chalmers RJ, Whale K, Colman G. The role of streptococcal infection in the initiation of guttate psoriasis. Arch Dermatol. 1992;128(1):39-42. doi:10.1001/archderm.1992.01680110049004
2. Garritsen FM, Kraag DE, de Graaf M. Guttate psoriasis triggered by perianal streptococcal infection. Clin Exp Dermatol. 2017;42(5):536-538. doi:10.1111/ced.13129
3. Gananandan K, Sacks B, Ewing I. Guttate psoriasis secondary to COVID-19. BMJ Case Rep. 2020;13(8):e237367. doi:10.1136/bcr-2020-237367
4. Saleh D, Tanner LS. Guttate psoriasis. In: StatPearls. StatPearls Publishing; 2021. Accessed May 5, 2021. https://www.ncbi.nlm.nih.gov/books/NBK482498/
5. Dupire G, Droitcourt C, Hughes C, Le Cleach L. Antistreptococcal interventions for guttate and chronic plaque psoriasis. Cochrane Database Syst Rev. 2019;3(3):CD011571. doi:10.1002/14651858.CD011571.pub2/full