Herpes Simplex Virus: a Marker of Severity in Bacterial Ventilator-associated Pneumonia

Purpose: Ventilator-associated pneumonia (VAP) is the most frequent nosocomial infection in intensive care units and has a high morbidity and mortality rate. It is mainly a bacterial disease, although the potential role of viruses as pathogens or copathogens in VAP is under discussion. Our study aims were to determine the incidence of herpes simplex virus (HSV) in the lower respiratory tract (LRT) secretions in patients with bacterial VAP and to assess its potential clinical relevance.

Material And Methods: This is a prospective observational study carried out over a 14-month period. All LRT samples of adult patients with VAP were sent for bacterial culture and virus isolation. We compared patients with bacterial VAP with isolation of HSV and those without.

Results: One-hundred seventy-seven patients had confirmed bacterial VAP. Herpes simplex virus was present in 13.4% of them. Patients with HSV had more severe underlying conditions and worse outcome. They consumed more antibiotics for the VAP episode, had more Clostridium difficile infection, spent a longer time on mechanical ventilation, had a longer intensive care unit and hospital stay, and had greater mortality than those without.

Conclusions: Herpes simplex virus excretion in LRT secretions is not infrequent in VAP, and it is associated with greater severity and worse prognosis.