Shia is a 32-year-old receptionist who presents with blue discolouration affecting her feet and causing staining on the inside of her shoes for the past month.

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Shia is a 32-year-old receptionist who presents with blue discolouration affecting her feet and causing staining on the inside of her shoes for the past month.

She has noted similar staining on her bedsheets. This has been most marked on hot days.