[Streptococcal perianal dermatitis and guttate psoriasis].

The link between guttate psoriasis and streptococcal infection is acknowledged. This form of psoriasis generally follows pharyngitis, but a small number of cases have been described as being triggered by a streptococcal infection other than in the throat. We report the case of a child with streptococcal anitis followed by guttate psoriasis. A 4-year-old boy presented painful perianal erythema present for two weeks with diffuse lesions of guttate psoriasis present since the second week. Group A beta-haemolytic streptococcus was found during bacterial examination of the anal region. After one month of antibiotic treatment with josamycin combined with daily application of desonide 0.05% topical cream, all symptoms subsided without relapse in the ensuing 6 months. This case demonstrates the need for careful clinical examination, both of the nose and throat but also of the perianal region, in children consulting for guttate psoriasis. It also demonstrates the strong link between guttate psoriasis and streptococcal infections in certain patients.