[Familial psoriasis: descriptive report of 9 families]. / Le psoriasis familial: etude descriptive à propos de 9 familles.

BACKGROUND: Psoriasis is a chronic inflammatory skin disease. The familial nature of psoriasis has long been recognized. Aim of our study was to describe the epidemiological, clinical and genetic features of familial psoriasis. METHODS: Through a prospective study we investigated during a study period of lyear (2006-2007) 9 Tunisian unrelated multiplex families. Patients with psoriasis and their available family members were examined by the same dermatologist. RESULTS: Thirty nine individual presented psoriasis (25 men and 4 women), with a mean age at onset about 19.8 years. With the systematic exam of member's family we discover 11 cases of unknown psoriasis. The common form of psoriasis was the preponderant one (37 cases). The nails, the scalp, the mucous membranes were involved respectively in 21, 12 and 13 cases. The psoriasis was severe in 11 cases. CONCLUSION: Through this study we find similar epidemiological and clinical features of those reported previously. The intra and inter-familial variability was evident in our patients.