Cytoid, colloid and large intra-blister round bodies and c-ANCAs in a case of erythema multiforme

摘要

Erythema multiforme is an acute, often self-limited and occasionally lethal syndrome with distinctive skinlesions and/or mucosal lesions; the disease has multiple triggers, including medications. We describe a 68 year oldAfrican American female on multiple medications; the patient suddenly presented with recurrent, flaccid bullae anderythematous circular lesions on her face, neck, genitals, hands and legs. Biopsies for hematoxylin and eosin (H&E)examination, direct immunofluorescence (DIF) and immunohistochemistry (IHC) stains were performed. The histologydisplayed erythema multiforme with epidermal blisters, defragmented melanocytes and other cell debris inside theblister. DIF revealed deposits of IgG, IgM, IgA, IgD, Complement/C3, C4, and fibrinogen within the epidermis;and around upper dermal vessels. Anti-neutrophil cytoplasmic antibodies (c-ANCAS) were present as part of “largeround bodies” inside the blisters, and as part of both cytoid and colloid bodies. Staining for Von Willembrand factor,CD68, myeloperoxidase and CD45 was seen on cell fragments within the blisters, as well as within the inflammatoryinfiltrate in the dermis. In this case cystoid, colloid and “large round bodies” may represent amalgamations of multiplecell fragments, with immunoglobulins and complement. Overall, a strong immunologic response was observed withc-ANCAs, caused by multiple medications.