Multiple Scattered Purpuric Vesicles: Challenge
A 71-year-old male of Asian origin, presented to Dermatology with a four-year history of intermittent scattered pruritic blisters, involving predominantly his upper and lower limbs. He has a background medical history of type-2 insulin-dependent diabetes, ischaemic heart disease, and late onset asthma diagnosed in his 60's. He was commenced on oral prednisolone 5 mg daily by his general physician for presumed pompholyx eczema. All of his other medications were long-standing and predated his skin eruption. On examination, he had scattered blisters with a large 4 cm tense bulla on his right plantar foot (Fig. 1), which limited his ability to walk. He also had scattered erythematous, inflammatory plaques on his knees, thighs, and forearms with necrotic and purpuric vesicles present on his hands (Fig. 2).
Initial laboratory investigations showed a normal full blood count, normal eosinophil count, renal, and liver profile. His ESR was 19 and CRP 5. His ANA was positive 1:80 and ENA negative. His porphyrin screen was negative.