Oral erythema multiforme: a 20 years clinical experience

Background: Erythema multiforme (EM) is a group of rare, acute, immune-mediated disorders which can affect the skin and/or the mucous membrane with a wide range of severity and extension. The development of EM has been linked by medical literature to numerous factors such as viral infections and drugs. The primary objective of this study is to present a retrospective multicenter case series describing sixty cases of patients affected by oral EM. Case summary: Our study revealed thirty one male (52%) and twenty-nine female with a mean (±SD) age at the time of diagnosis of the disease of 37.9 (± 18). The patient age range was 7–78 years, although over 70% of all subjects were between 20 and 50 years old. The age differences between male (36 ± 16) and female (40 ± 19.5) were not significant. The mean duration of EM outbreaks was 7 ± 6 days. Twenty nine patients (48%) had no previous outbreaks. Twenty two patients (37%) developed two or more previous outbreaks. Drugs were suspected as precipitants in twenty eight patients (46.7%). Herpes virus infections could have been the triggering factor in 18 patients (30%) though in two of these cases also a history of medication use was present. About the sites, in nine patients (15%) other mucosas were involved (5 genital, 3 ocular, 1 nasal) and twenty-five patients (42%) had also skin lesions. Fifty-one patients (85%) were classified as presenting minor EM, nine (15%) presented major forms of the disease. Conclusions: Our analysis revealed that medication use is the most triggering factor followed by herpes viral infections. The oral mucosa is the most frequently affected mucosal region in EM. In the oral cavity the buccal mucosa, the lips and the tongue are the most affected sites with a clinical presentation mainly represented by ulcerative forms with hematic crusts.