A 40 year old dentist presents with the skin lesion shown above, pain, and low grade fever. To make the diagnosis, you remove the blister roof with a no. 15 blade, blot excess fluid, then scrape the base with a scalpel blade. You spread the material on a slide, add 95% methanol for 5 seconds, air dry for 1-2 minutes, then add a nuclear stain for 30-60 seconds. Finally, you wash with distilled water and restain with methanol. Here is what you see:
Challenge: What's the diagnosis?
1. What stain was that?
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