HHV-6 infection of tonsils and adenoids in children with hypertrophy and upper airway recurrent infections

Objective: Human herpes virus 6 (HHV-6), the agent of a self-limiting exanthematic disease in childhood, persists in a silent state in the secondary lymphoid organs and the reactivation is characterized by HHV-6-induced inflammatory cytokines. This study investigates the possible etiological role of HHV-6 in children affected by tonsil and adenoid hypertrophy. Methods: 55 tonsils, 80 adenoids fresh tissues and 74 blood samples were collected from 80 children (mean age 4.8 years, 43.5% female) undergoing elective tonsillectomy and/or adenoidectomy for tissue hypertrophy. Moreover, patients with 6 cells suggesting a latent/persistent phase of infection. Conclusion: These results reinforce the role of the secondary lymphoid organs as an important reservoir for HHV-6B. Nevertheless, infection of lymphoid cells, sustained by a low level of replication, could be sufficient to increase the local injury through an autologous mechanism of inflammation.