We report a case of Papillon-Lefèvre syndrome in a patient aged 26 in whom the familial genetic study showed close consanguinity among the parents. Oral treatment with aromatic retinoid during 6 weeks provided nearly total healing of the cutaneous lesions. Among the explorations carried out, attention must be paid to the lessening of chemotactic factors in the blood serum. Throughout his life, the patient suffered pronounced bacterial infectious processes, the last being especially severe and leading rapidly to death.