Pseudoherpetic grover disease: report of 2 cases and review of the literature.

Two cases of a pseudoherpetic variant of Grover disease are presented. The first patient was a 60-year-old woman who had high fevers in combination with right lower lobe pneumonia. She developed an itchy papulovesicular rash on her back and upper abdomen. The second patient was a 68-year-old woman who while bedridden developed an itchy papulovesicular rash on her back. Vesiculobullous forms of dermatitis were clinically suspected in both cases, and herpetic vesicles were the lead diagnosis in one case. Pathologically, lesions from both patients revealed intraepidermal fluid-filled vesicles that at scanning magnification raised the suspicion of herpetic lesions. At higher magnification, acantholytic cells, some seemingly multinucleated, could be ppreciated. However, immunohistochemistry for herpes simplex virus and varicella zoster virus antigens proved negative. Moreover, some of the lesional cells revealed dyskeratosis more typical of the spongiotic/vesicular variant of Grover disease, and accordingly, this diagnosis was eventually established in both patients. Recognition of the pseudoherpetic variant of spongiotic/vesicular Grover disease is important in determining correct treatment, and therefore, subtle clues to its diagnosis should be sought in evaluation of such lesions.