Preemptive acyclovir to prevent herpes simplex virus bronchopneumonitis in mechanically ventilated patients with herpes simplex virus oropharyngeal reactivation: An ancillary study of the preemptive treatment for herpesviridae trial

Background To evaluate the impact of preemptive acyclovir treatment on herpes simplex virus (HSV) bronchopneumonitis in mechanically ventilated patients with HSV oropharyngeal reactivation. Methods Ancillary study of the Preemptive Treatment for Herpesviridae (PTH) clinical trial. Patients included in that trial from one centre (Pitié-Salpêtrière Hospital) and in whom at least one bronchoalveolar lavage (BAL) was performed for ventilator-associated pneumonia suspicion were included in the present study. Rate of HSV bronchopneumonitis, defined as clinical symptoms suggesting of pneumonia and presence of HSV in BAL fluid ≥105 copies of HSV/106 cells, were compared in patients who received either acyclovir or placebo. Results Eighty-three patients were included; 40 having received preemptive acyclovir and 43 having received a placebo, without differences between groups at admission or at randomization. The number of patients who developed HSV bronchopneumonitis was lower among acyclovir-treated patients than among placebo-treated patients (40% vs. 72%, respectively, p = .003). Results were similar when restricted to patients without HSV detected in the lower respiratory tract at randomization (31% vs. 61%, respectively, p = .03). Conclusions Preemptive acyclovir treatment in mechanically ventilated patients with HSV oropharyngeal reactivation reduces HSV bronchopneumonitis rate.