[Retrospective analysis of the four kinds of virus in adeno tonsillar tissues from children using PCR].

Objective: To investigate the seasonal disturbations and the rates of detection of EpsteinBarr virus (EBV), Human Bocavirus(HBoV), and polyomaviruses KI and WU (KIPyV and WUPyV) in adenoid and tonsil tissues during the absence of acute infection symptoms. Method: DNA expressions of EBV, HBoV, polyomaviruses KIPyV and WUPyV were investigated in children with chronic tonsillar and adenoidal diseases using real time polymerase chain reaction. The patients were divided into three group: adenoid group, chronic tonsillit group and hypertrophic tonsillitis group. The relationships of the expressions of these viruses with age, gender, recurrent infection and airway obstruction were analyzed. Seasonal variations in rates of detection of these viruses in adenoid and tonsil tissues were also investigated. Result: Considering adenoid specimens, HBoV was found to be the most frequent virus with the rate of 43.1%. In specimens of chronic tonsillitis and hypertrophic tonsils, EBV was the most frequently encountered virus (53.8%, and 32.0%, respectively). In children with hypertrophic adenoids, while HBoV was detected to be positive throughout the year, EBV was present throughout the year in children with recurrent tonsillitis. Conclusion: The detection of HBoV and EBV throughout the year in samples of children with asymptomatic chronic adenotonsillar diseases may indicate that these viruses may remain persistently in lymphoepithelial tissues of upper respiratory tract. Virus persistence may have a pathogenetic potential for development of lymphoid hypertrophy and a chronic stimulatory effect for inflammation.