Behçet's disease (BD) is a multi-system inflammatory disorder dominated clinically by recurrent oral and genital ulceration, uveitis, and erythema nodosum. Behçet's disease runs a chronic course, with unpredictable exacerbations and remissions whose frequency and severity may diminish with time. Behçet's disease typically arises in young adults, although childhood-onset BD has also been reported. The disease can affect both genders and has a worldwide distribution, although it is more prevalent in countries of the ancient Silk Route. The cause of BD remains unknown, although an autoimmune reaction triggered by an infectious agent in a genetically predisposed individual has been suggested. The treatment of BD is symptomatic and empirical, but generally specific to the clinical features of each patient. The majority of affected individuals do not have life-threatening disease, although mortality can be associated with vascular-thrombotic and neurological disease.

Immunosuppression and antiviral prophylaxis may interact to influence the spectrum of oral HHV-8 strains and the extent of post-transplantation HHV-8 shedding into the mouth.

Renal allograft recipients in the Middle East are at high risk of developing Kaposi's sarcoma. This report describes the extent of oral human herpesvirus 8 shedding and the genomic diversity of the virus in five Saudi Arabian kidney transplantation patients in whom Kaposi's sarcoma had developed. PCR protocols were applied to amplify three fragments of the viral genome from whole-mouth saliva, parotid saliva, buccal and palatal exfoliates, plasma, peripheral blood leukocytes and biopsy of the Kaposi's sarcoma lesion, and to quantify the viral load in whole-mouth saliva. Viral DNA was detected in all plasma and biopsy samples, 80% of whole-mouth saliva, 20% of each of the other oral samples, and none of the leukocyte samples. The viral load in the cell-free fraction of whole-mouth saliva ranged between approximately 1.2 x 10(3) and 2.2 x 10(6) genome-copies/ml. Genotypically distinct viral strains were evident: intra-lesionally in 1 patient; intra-orally in one patient; between an oral sample and biopsy in two patients; and in four patients, between an oral sample and plasma, and between plasma and biopsy. Thus, in the patients studied, salivary shedding of human herpesvirus 8 was frequent and could be extensive, and they were prone to multiple infections. Measures to curtail salivary viral transmission to pre- and post-transplantation patients might reduce the incidence of post-transplantation Kaposi's sarcoma.