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Pityriasis rosea — SCE Dermatology MCQ

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HardGeneral dermatology & dermatology in primary health carePityriasis roseaSCE Dermatology

A 58-year-old woman has fragile blistering skin and milia on the dorsal hands. Urine uroporphyrins are markedly raised; ferritin is 680 micrograms/L, transferrin saturation 67%, haemoglobin 151 g/L and HFE testing shows C282Y homozygosity. Which disease-directed plan is most appropriate?

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Reveal the answer and explanation

Correct answer: C — Undertake repeated venesection with iron-index monitoring and address hepatic triggers

Explanation lettering: E = shown as B · B = shown as C · C = shown as D · D = shown as E

B is correct. The phenotype and porphyrin pattern indicate porphyria cutanea tarda, and the marked iron excess with C282Y homozygosity makes repeated venesection an appropriate disease-directed treatment while ferritin, haemoglobin and liver status are monitored. Alcohol, oestrogen exposure, hepatitis C and other hepatic contributors should also be addressed. Hydroxychloroquine can mobilise hepatic porphyrin, but PCT requires a deliberately low-dose regimen; standard daily antimalarial dosing can provoke acute hepatic injury. Narrowband UVB does not remove hepatic porphyrin, beta-carotene is associated with erythropoietic protoporphyria rather than iron-loaded PCT, and trigger avoidance alone is insufficient when active disease and substantial iron overload are present.

Reference: British Association of Dermatologists: porphyria cutanea tarda: https://www.bad.org.uk/pils/porphyria-cutanea-tarda