[Exudative erythema multiforme around nevi].

Actas Dermosifiliogr. 2009;100:329-43 333 To the Editor: There are several types of dermatosis that may occur around the melanocytic nevi, although there are few reported cases of each of these. The most representative of these dermatoses is halo nevus1 (Sutton nevus, leucoderma acquisitum centrifugum), but there are other named examples including Meyerson nevus2 (halo dermatitis), targetoid nevus,3 and a form of exudative erythema multiforme around the nevi (nevocentric EEM).4 The most common nevocentric dermatosis is Sutton nevus or halo nevus,1 recognized by the presence of a colorless halo around the nevus that has been related to an immunological process caused by the nevus itself. In 1971, Meyerson2 described some patients with scaly erythema around the nevi—confirmed by histology to be a spongiotic dermatitis—that resolved spontaneously.5,6 Targetoid halo nevus is another condition reported around melanocytic nevi—this is believed to be an immune phenomenon caused by halo nevus that resolves following removal of the nevus.3 There is also one case of nevocentric psoriasis described by Shifer et al7 in 1992. There are very few cases of nevocentric EEM reported in the literature, and, unlike the case of our patient, none of them occurred during pregnancy. Humphreys and Cox8 described one case of unknown etiology in 1988 in a patient treated with thiabendazole, but no later case has been related to any other drug. All the cases described have been related to a history of labial herpes, as was the case in our patient. In all the cases described, histology confirmed the presence of a lymphocytic infiltrate in the dermis around the nevi cells, along with keratinocytic degeneration and necrosis in the epidermis, suggestive of nevocentric EEM.4,8-10 The progression of this disease is identical to that seen in non-nevocentric EEM, which resolve spontaneously or following treatment with corticosteroids. Some authors use antiviral agents to accelerate healing in herpes, an option we did not consider for our patient. We present the case of a woman in the fifth month of gestation, with no relevant history except for recurrent labial herpes, who consulted because of redness around several nevi. This initially consisted of halos of erythematous infiltrates covering an area 0.2 cm in diameter around the nevi; as time progressed these changed into concentric targetoid halos around most of the nevi on the body and face (Figures 1 and 2), with some isolated targetoid lesions in areas where there was no nevus. The patient reported lesions on the upper lip compatible with labial herpes in remission. Clinical and histological study enabled diagnosis of nevocentric EEM. Prednisone 30 mg/d was prescribed and the lesions disappeared within 5 days.