Respiratory viral infection in immunocompromised patients

Introduction: Knowledge on viral infections in immunocompromised patients is sparse. We investigated the incidence of respiratory viruses in a well-characterized population of immunocompromised patients. Methods: All immunocompromised patients with suspicion of infection and/or respiratory symptoms and/or radiologically confirmed lung infiltrates undergoing bronchoscopy were included in the study. In addition to the routine assessment of bronchoalveolar lavage fluid, a multiplex PCR for 20 viruses has been performed. Study period was from October 2009 to September 2017. Results: 1303 patients with 2666 samples were included in the study. 35% of the samples were positive for viral infection, 23% were positive for bacterial infection, 1.6% were positive for atypical mycobacteria, and 10% were positive for fungal infection. Bacterial coinfection was evident in 26% and fungal coinfection in 13% of the virus-positive samples. The incidence of respiratory viruses was as follows: adenovirus 3.0%, bocavirus 1.1%, coronavirus 8.9%, human metapneumovirus 6.6%, H1N1 0.53%, influenza 6.1%, parainfluenza 10.3%, rhinovirus-enterovirus 35.4%, and RSV 8.2%. Other viruses included cytomegalovirus 25.1%, Epstein-Barr virus 0.85%, herpes simplex virus 12.6%, human herpes virus-6 0.32%, human herpes virus-7 0.1% and varicella-zoster virus 0.1%. Anti-viral therapy was started in approximately 5.6% of the cases, continued in 17.0% and stopped in 0.4% of the cases. Conclusion: There is a high prevalence of respiratory virus infections in immunocompromised patients undergoing diagnostic bronchoscopy for respiratory symptoms. This finding may influence patient management.