PMC9532255_01
Large dark red patches can be seen on the back of the buttocks, with a large number of silver-white scales attached to them, most of which are fused into pieces, which are map-shaped and annular, and local skin lesions show lichen-like changes.
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The patient visited our hospital in November 2019 (Figure 1) and was diagnosed with severe plaque psoriasis.
Erythematous scales on the buttocks and back basically subsided, leaving hazel pigmentation.
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A re-examination in June 2020 showed that the systemic rash had generally resolved (Figure 2).
A large, diffuse dark erythema on the back of the buttocks with thickened skin and bright red margins, scales and hyperpigmentation.
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An examination in August 2021 revealed a scald-like rash on the buttocks and back (Figure 3) accompanied by redness, swelling, heat, pain, occasional nausea and vomiting, poor appetite, and delayed response.
The erythema infiltration of the buttocks was aggravated, and part of the skin was pink and the pain was severe.
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The rash continued to worsen over 4 days (Figure 4).
The redness and swelling subsided, the pain was relieved, and a large area of pigmentation remained.
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The patient was re-examined 10 days later; he was found to have significant regression of the redness and swelling, with large patches of residual pigment deposition (Figure 5).