[Gougerot Sjögren syndrome and hepatitis C virus: what relation?].

The incidence of Sjogrëns syndrome (SS) in patients with chronic liver disease and that of hepatitis C in mixed cryoglobulinemia strongly-suggest a link between the hepatitis C virus (HCV) and SS. A recent report has also demonstrated typical lymphocyte sialadenitis in HCV-positive subjects, raising a question concerning the classical definition of SS. Do patients with HCV and lymphocyte sialadenitis have SS? If the problem of variable diagnostic criteria can be overcome (for example by using the criteria established by the European study group) it can be concluded that the proportion of HCV+ patients with SS is related to female sex, age (perimenopause period in women), and liver histology rather than fibrosis, but not with duration of the liver disease, nor cirrhosis or viral genotype. The second question is to determine whether the observed focal lymphocyte infiltration of the salivary glands is typical of SS. As routine biopsy results lack specificity and sensitivity, immunohistochemistry is required to identify T8 predominance distinctive of SS. Results obtained to date suggest that the T8 sialadenitis might result from an autoimmune mechanism and consequently that the SS-HCV association might either be a coincidence between the two relatively frequent diseases or on the contrary that HCV plays a pathogenic role in SS. The major argument for the latter hypothesis would be the demonstration of HCV within the salivary gland epithelial cells. As HCV-positive immunohistochemistry tests on salivary biopsies may simply indicate presence of HCV in the blood stream at the time of biopsy, more sophisticated in situ PCR methods are currently being applied in an attempt to obtain objective evidence which could incriminate HCV infection of the salivary glands as a causal agent in Sjogrëns syndrome.