Frequency of EBV-DNA detection in Sjogren's syndrome

[Prevalence of Epstein-Barr virus in Sjögren's syndrome in Tunisia]

PURPOSE

The cause of Sjögren's syndrome is unclear. Several studies suggested the role of Epstein-Barr virus (EBV) in the pathogenesis of this syndrome, but this always remains a subject of numerous controversies. The purpose of this study was to evaluate the prevalence of EBV in Sjögren's syndrome in Tunisia.

METHODS

A series of 31 paraffin-embedded biopsies of salivary glands from patients with Sjögren's syndrome were studied in comparison with 19 control glands. EBV was investigated by PCR, EBERs in situ hybridization and by immunohistochemistry for the detection of LMP1, EBNA2 and ZEBRA.

RESULTS

EBV DNA was detected by PCR in 3 of 22 PCR beta-globin positive Sjögren's syndrome cases (13.6%) and in 2 of 17 PCR beta-globin positive control glands (11.7%); in situ hybridization positivity was noted in rare lymphocytes in the 3 EBV positive cases of Sjögren's syndrome, but not in control glands; immunohistochemical study was negative in all cases.

CONCLUSION

EBV infection does not appear to play a significant role in the pathogenesis of Sjögren's syndrome in Tunisia.

Histopathological analysis and demonstration of EBV and HIV p-24 antigen but not CMV expression in labial minor salivary glands of HIV patients affected by diffuse infiltrative lymphocytosis syndrome

BACKGROUND

The diffuse infiltrative lymphocytosis syndrome (DILS) in HIV patients is characterized by the persistence of CD8-circulating lymphocytes and lymphocytic infiltration, predominantly in salivary glands.

METHODS

We examined seven HIV-positive patients with bilateral parotid enlargement and sicca symptoms. Minor labial salivary gland biopsies were performed in all patients and submitted for histopathological analysis and immunohistochemistry for CD4, CD8, cytomegalovirus (CMV), LMP-EBV protein, and HIV p-24 protein.

RESULTS

In all cases, lymphocytic infiltration of the minor salivary glands, mainly periductal, was found. Acinar atrophy, ductal ectasia, and mild to moderate fibrosis were also observed. We noticed strong immunohistochemical reaction for LMP-EBV and p-24 proteins in ductal cells in all cases, while staining for CMV was consistently negative. The lymphocytes were positive for CD8, but consistently negative for CD4.

CONCLUSIONS

A role of Epstein-Barr virus (EBV) and HIV, but not CMV, in the pathogenesis of DILS, is suggested by our immunohistochemical findings.

Detection of Epstein-Barr virus in salivary gland specimens from Sjögren's syndrome patients

The cause of Sjögren's syndrome remains unclear, but several environmental and genetic factors have been implicated. The Epstein-Barr virus (EBV), among others (e.g., cytomegalovirus, human herpesvirus 6, and retroviruses), has been widely studied in connection with Sjögren's syndrome without conclusive results. To determine the role of EBV infection in patients with Sjögren's syndrome, the presence of EBV deoxyribonucleic acid (DNA) in major and minor salivary gland biopsy specimens was investigated by means of sulfur 35 in situ hybridization and polymerase chain reaction. Additionally, the presence of latent virus proteins EBV latent membrane protein and Epstein-Barr nuclear antigen 2 was analyzed by immunohistochemical methods. Viral DNA, detected by in situ hybridization, was found in 19% of patients with a diagnosis of Sjögren's syndrome and in 3% of controls. All tissues studied were found to be negative for EBV DNA by polymerase chain reaction. EBV latent membrane protein-positive staining was seen in 17% of patients and 22% of control subjects, while Epstein-Barr-positive staining was found in 25% of patients and 39% of controls. The low frequency of EBV DNA detected in the biopsy specimens does not indicate that the virus itself is the cause of Sjögren's syndrome. However, the possibility that the virus acts as a cofactor cannot be ruled out.

Viral infections in the immunocompetent patient

Human herpesviruses and human papillomaviruses are ubiquitous and may cause an array of oral disease. Herpesviruses are unique because recurrent localized disease occurs after the primary infection. Human papillomaviruses are known for their ability to produce benign epithelial proliferations and increasingly are implicated in the development of oral cancer. This article reviews the pathogenesis of common oral lesions induced by these viruses.