[Baker Rosenbach erysipeloid appearing as a granulomatous cheilitis]

Baker-Rosenbach's erysipeloid is a skin infection caused by Erysipelothrix rhusiopathiae. It occurs essentially in humans exposed to animals colonized with this germ such as swine. The typical skin lesion, an erythematous macule generally localized to inoculation site, frequently in the extremities, quickly resolves spontaneously. The lips are an atypical site of this infection. We describe a case of chronic granulomatosis cheilitis in a farmer caused by E. rhusiopathiae.

A 40-year-old farmer, a wild-boar hunter and chronic smoker with no history of tuberculosis, injury or insect bites, presented at our dermatology unit with ulcerative macrocheilitis of the lower lip ongoing for 1 year. Its surface was purulent. A biopsy specimen showed non-caseating epithelioid granulomas. Laboratory and radiological screening for tuberculosis, sarcoidosis and Crohn's disease, and parasitological examination for Leishmaniasis proved negative. Bacteriological examination identified E. rhusiopathiae and labial Baker-Rosenbach's erysipeloid was diagnosed. The lesion healed after 15 days of treatment with parenteral penicillin G (12m IU/d), totally disappearing after 3 months.

Swine erysipelas usually occurs in man as Baker-Rosenbach's erysipeloid. This localized form of infection with E. rhusiopathiae is the most frequent and the lesion typically observed is a violaceous plaque, less inflammatory with induration; spontaneous regression occurs after a mean 3 months. To our knowledge, this case is the first report of ulceration associated with macrocheilitis. Histologically, the granuloma directed our investigation towards the principal aetiologies of granulomatosis cheilitis, such as tuberculosis considering the epidemiological context, sarcoidosis or Crohn's disease. The diagnosis of erysipeloid was supported by epidemiological evidence (occupational exposure), isolation of the germ at the lesion and its regression on treatment with penicillin G.

Diagnosis of E. rhusiopathiae infection was confirmed by bacteriology. However, the hypothesis concerning the pathogenesis of its chronic course in our patient remains a subject of discussion.