Lesion of Merit
Psoriasis is a common skin disorder with a wide range of clinical manifestations. Variants of the disease include chronic plaque, erythrodermic, inverse, guttate, pustular and nail. The characteristic presentation is the development of inflammatory plaques of the skin. Guttate psoriasis (GP) is more prevalent in children and young adults, and many cases occur two to three weeks after streptococcal or viral upper respiratory infection.
Psoriasis affects 0.6-4.8 percent of the population, and less than 30 percent of these cases are GP. Guttate psoriasis is more common under age 30, and younger ages are more likely to be affected by the guttate variant. It affects both males and females with no general predominance.
GP normally presents with an acute onset of one to numerous well-demarcated, scaling, erythematous papules and plaques ranging in size from 2 to 15mm in diameter with a fine, adherent scale. "Guttate" refers to the discrete drop-like appearance of the lesions. It typically affects the trunk and proximal extremities, but can include the face, scalp, hands and feet. Generally, the palms of the hands and the soles of the feet are excluded. Lesions may or may not be pruritic.
The rash may present as a new disorder in patients without a history of psoriasis, or as a new presentation of the disease in patients with chronic plaque psoriasis. The diagnosis is made clinically, with biopsies occasionally used to confirm cases. There is no definitive serologic test for GP. Routine tests for streptococcal infection are controversial and may not be necessary without signs of strep infection. However, many patients do also have positive antistreptolysin O titers. Appropriate testing should be completed in patients with signs and symptoms of strep pharyngitis in order to treat the underlying condition.
Differential diagnosis for GP includes: nummular dermatitis, pityriasis lichen oides chronic, pityriasis rosea, small plaque parapsoriasis, secondary syphilis, tinea corporis, viral exanthems and morbilloform drug eruptions.
Class I human leukocyte antigen HLA-Cw6 and beta hemolytic streptococci are the primary linked factors to the disease. New cases of GP are preceded by streptococcal pharyngitis in 56-97 percent of patients and can include perianal streptococcal infection in children. It typically shows up two to three weeks after these infections or other viral upper respiratory infections. This correlation is more common in new cases, but patients already affected by chronic plaque psoriasis can acquire GP. It can also occur after varicella, Pityrosporum folliculitis, at tattoo sites and after tumor necrosis factor alpha therapy.
Treatment for GP is similar to chronic plaque psoriasis. Spontaneous recovery may occur in weeks to months. Some patients may elect for no treatment. Phototherapy, including narrowband UVB, broadband UVB, psoralen plus UVA and even five to 10 minutes of prime outdoor sun exposure without sunblock can improve GP. Topical treatments include topical corticosteroids once to twice daily for two weeks, and vitamin D analogs, such as calitriol and calcipotriene. These treatments can be used alone or in conjunction. GP is more responsive to therapy than chronic plaque psoriasis. For patients with recurrent GP, tonsillectomy and chronic plaque psoriasis systemic immunomodulatory and immunosuppressive treatments have been used. Systemic therapy is the next line treatment if the above topical medications do not improve the condition. Antibiotics are controversial, and data to support their use is not sufficient. However, active streptococcal infections should be treated as indicated.
Discussion
Psoriasis is a common skin disorder with a wide range of clinical manifestations. Variants of the disease include chronic plaque, erythrodermic, inverse, guttate, pustular and nail. The characteristic presentation is the development of inflammatory plaques of the skin. Guttate psoriasis (GP) is more prevalent in children and young adults, and many cases occur two to three weeks after streptococcal or viral upper respiratory infection.
Psoriasis affects 0.6-4.8 percent of the population, and less than 30 percent of these cases are GP. Guttate psoriasis is more common under age 30, and younger ages are more likely to be affected by the guttate variant. It affects both males and females with no general predominance.
GP normally presents with an acute onset of one to numerous well-demarcated, scaling, erythematous papules and plaques ranging in size from 2 to 15mm in diameter with a fine, adherent scale. "Guttate" refers to the discrete drop-like appearance of the lesions. It typically affects the trunk and proximal extremities, but can include the face, scalp, hands and feet. Generally, the palms of the hands and the soles of the feet are excluded. Lesions may or may not be pruritic.
The rash may present as a new disorder in patients without a history of psoriasis, or as a new presentation of the disease in patients with chronic plaque psoriasis. The diagnosis is made clinically, with biopsies occasionally used to confirm cases. There is no definitive serologic test for GP. Routine tests for streptococcal infection are controversial and may not be necessary without signs of strep infection. However, many patients do also have positive antistreptolysin O titers. Appropriate testing should be completed in patients with signs and symptoms of strep pharyngitis in order to treat the underlying condition.
Differential diagnosis for GP includes: nummular dermatitis, pityriasis lichen oides chronic, pityriasis rosea, small plaque parapsoriasis, secondary syphilis, tinea corporis, viral exanthems and morbilloform drug eruptions.
Class I human leukocyte antigen HLA-Cw6 and beta hemolytic streptococci are the primary linked factors to the disease. New cases of GP are preceded by streptococcal pharyngitis in 56-97 percent of patients and can include perianal streptococcal infection in children. It typically shows up two to three weeks after these infections or other viral upper respiratory infections. This correlation is more common in new cases, but patients already affected by chronic plaque psoriasis can acquire GP. It can also occur after varicella, Pityrosporum folliculitis, at tattoo sites and after tumor necrosis factor alpha therapy.
Treatment for GP is similar to chronic plaque psoriasis. Spontaneous recovery may occur in weeks to months. Some patients may elect for no treatment. Phototherapy, including narrowband UVB, broadband UVB, psoralen plus UVA and even five to 10 minutes of prime outdoor sun exposure without sunblock can improve GP. Topical treatments include topical corticosteroids once to twice daily for two weeks, and vitamin D analogs, such as calitriol and calcipotriene. These treatments can be used alone or in conjunction. GP is more responsive to therapy than chronic plaque psoriasis. For patients with recurrent GP, tonsillectomy and chronic plaque psoriasis systemic immunomodulatory and immunosuppressive treatments have been used. Systemic therapy is the next line treatment if the above topical medications do not improve the condition. Antibiotics are controversial, and data to support their use is not sufficient. However, active streptococcal infections should be treated as indicated.