[Comparative epidemiology of pemphigus in Tunisia and France. Incidence of foliaceus pemphigus in young Tunisian women].

Introduction: Recent studies have suggested that pemphigus foliaceus is quite frequent in young Tunisian women. In order to confirm this hypothesis, we compared the incidence of pemphigus in general in Tunisia with that in the Ile-de-France region.

Method: All new cases of pemphigus diagnosed during a 6-year period were reviewed in our dermatology and pathology laboratories. These cases were classed as pemphigus foliaceus or pemphigus vulgaris on the basis of histology reports.

Results: In France, the incidence was 1-7 new cases per million per year (95 p. 100 confidence interval 1.4-2.1). Pemphigus vulgaris was diagnosed in 73 p. 100 of the cases with an incidence increasing with age. Sex ratio (F/M) was 1.2. The incidence observed in Tunisia was significantly higher than that observed in France with 6.7 new cases per million per year (95 p. 100 confidence interval 5.8-7.7). Pemphigus foliaceus was more frequent (61 p. 100), the sex ratio (F/M) was 4.1. Incidence was higher in young women, with 20 new cases of pemphigus foliaceus per million per year among women from 25 to 34 years of age. These levels were higher in rural desert areas. No familial cases were observed and only one case occurred in a child.

Discussion: These findings confirm the specific epidemiology of pemphigus in Tunisia, which appears to be similar and also different from that in Brazilian pemphigus. As in Brazil, there was a predominance of pemphigus foliaceus in young adults living in rural areas in poor socioeconomic conditions. However in Tunisia the disease predominates significantly in women and there are no familial and rare juvenile cases.