SECTION EDITOR: MARY S. STONE, MD; ASSISTANT SECTION EDITORS: SOON BAHRAMI, MD; CARRIE ANN R. CUSACK, MD; SENAIT W. DYSON, MD; MOLLY A. HINSHAW, MD; ARNI K. KRISTJANSSON, MD
Microscopic examination with hematoxylin-eosin showed a subepidermal blister with abundant neutrophils and dermal leukocytoclastic vasculitis. Direct immunofluorescence of the perilesional skin showed fibrin deposition on dermal small vessels, with negativity for other immunorreactants (IgG, IgM, IgA, and C3).
Additional blood test investigations showed an elevated erythrocyte sedimentation rate (106 mm/h; range, 1-20 mm/h), elevated titers of antineutrophil cystoplasmic antibodies against proteinase 3 (PR3-ANCA) (320 U/mL; reference range, <25 U/mL), and negative results for antimyeloperoxidase antibodies.
A 32-Year-Old Man With Grouped Papules and Vesicles—Diagnosis. Arch Dermatol. 2012;148(7):850. doi:10.1001/archderm.148.7.850-b