ABSENCE OF HELICOBACTER-PYLORI DNA IN SALIVARY LYMPHOEPITHELIAL LESIONS

Helicobacter pylori is a common cause of chronic gastritis and has bee n implicated as the main agent responsible for the development of lymp homas of mucosa associated lymphoid tissue (MALT) in the stomach. An u ncommon cause of salivary gland swelling is salivary lymphoepithelial lesion (SLEL), which shows histological features of aquired MALT and i s associated with the development of MALT-type lymphomas. Since H. pyl ori has been identified in the oral cavity, we hypothesised that this organism might act as a potential antigen for the development of MALT in salivary glands. Routinely processed biopsies of 20 SLEL were scree ned for H. pylori DNA using a sensitive two-stage PCR technique to amp lify the 16S ribosomal RNA gene. Immunoglobulin heavy chain gene monoc lonality was determined by amplifying the VDJ gene using a nested PCR technique. All SLEL had histological features of organised MALT and 14 cases showed Ig heavy chain gene monoclonality consistent with MALT l ymphoma. None of the SLEL contained H. pylori DNA. In contrast to the putative role of H. pylori as an antigenic stimulus in gastric MALT ly mphomas, it appears not to play a role locally in the development of M ALT or MALT lymphomas of the salivary gland.