Erythema and erosions of the perianal region in a 49‐year‐old man

Isolated Perianal Erosive Lichen Planus: A Diagnostic Challenge

“…A PubMed search of articles indexed for MEDLINE using the terms erosive or ulcerative and lichen planus and perianal revealed 10 cases of perianal erosive LP, and weak data exist regarding therapy (Table ). [8][9][10][11][12] Of these FIGURE 2. A, Histopathologic examination revealed acanthosis of the epidermis with slight compact hyperkeratosis, scattered dyskeratotic keratinocytes, and a dense bandlike lymphohistiocytic infiltrate that obliterated the dermoepidermal junction (H&E, original magnification ×10).…”

“…cases, only 3 reported isolated perianal involvement. [8][9][10] In most reported cases, perianal involvement manifested as extremely painful and occasionally pruritic, sharply angulated erosions and ulcers arising 0.5 to 3 cm from the anus with macerated, whitish, and violaceous borders. Most of the lesions occurred unilaterally, with only 1 case of bilateral perianal involvement.…”

“…Most of the lesions occurred unilaterally, with only 1 case of bilateral perianal involvement. 10 The differential diagnosis of perianal erosions is extensive and includes cutaneous Crohn disease, extramammary Paget disease, cutaneous malignancy, herpes simplex virus, cytomegalovirus, external hemorrhoids, lichen sclerosus, Behçet disease, lichen simplex chronicus, and drug-induced lichenoid reaction, among others. It is worth emphasizing infectious processes and cutaneous malignancies in light of our patient's immunosuppression.…”