Fig. 6

Histopathology of canine exfoliative cutaneous lupus erythematosus. a: cell-rich, lymphocytic interface dermatitis is present with a distinct band-like (lichenoid) dermal infiltrate of lymphocytes, plasma cells and a few histiocytes. 100X (b): in an area of well-developed interface dermatitis, laminated, orthokeratotic hyperkeratosis (exfoliation) is present, which is typical of the disease. 200X. c: lymphocytic interface folliculitis and mural folliculitis involve the infundibulum (upper-right) as well as the isthmus and inferior segments (lower-left) of hair follicles. Sebaceous glands are absent in this biopsy, as is reported in some cases. 200X (d): lymphocytic interface folliculitis and mural folliculitis are present in the external root sheath of anagen hair follicles. Telogen hair follicles can also be affected (not shown). 200X