Figure 1: (a-c) A representative case of erythema multiforme. (a) H&E staining, showing edematous, large eccrine sweat glands (black arrow) (200×) (b) DIF, using FITC conjugated antihuman fibrinogen; note positive staining around the same glands (green staining; white arrow) (c) PAS stain, showing mild positivity against the same glands (purple staining; black arrow). (d-f) A representative example of a drug eruption. (d) H and E staining showing edematous eccrine duct (black arrow) (400×) (e) PAS stain, showing positivity against a nearby eccrine gland glands (purple/red staining; black arrow) (f) DIF using FITC conjugated antihuman Complement/C3, and showing positive staining around the sweat glands (green staining). The nuclei of the cells were counterstained with DAPI in blue, and the blood vessels around the sweat gland stained with Ulex in red