DETECTION OF EPSTEIN-BARR-VIRUS AND HUMAN PAPILLOMAVIRUS TYPE-16 DNA IN HAIRY LEUKOPLAKIA BY IN-SITU HYBRIDIZATION AND THE POLYMERASE CHAIN-REACTION

Demonstration of Epstein-Barr virus (EBV) is considered desirable for the accurate diagnosis of hairy leukoplakia (HL). Previous studies hav e reported possible associations with human papillomavirus (HPV) infec tion although this is not a universal finding. Presence of EBV and HPV 16 was examined in biopsy specimens from 18 cases of HL and ten contr ol specimens by in situ hybridisation using digoxigenin-labelled synth etic oligonucleotide probes and by the polymerase chain reaction (PCR) . The presence of EBV was demonstrated in 12 cases by both techniques. Of the remaining six cases EBV could be detected in three by in situ hybridisation but not by PCR; EBV was not detected by either method in a further three cases. All samples were negative for HPV 16 by both t echniques under conditions of high stringency, although when stringenc y of in situ hybridisation was reduced, four samples appeared to harbo ur HPV DNA sequences. This study provides further evidence to support the role of EBV in the pathogenesis of HL and suggests that HPV 16 is not regularly encountered.