Association of Dynamics of Anellovirus Loads With Hospital-Acquired Pneumonia in Patients With Brain Injury During the Intensive Care Unit Stay

Background: Critical illness induces immune disorders associated with an increased risk of hospital-acquired pneumonia (HAP) and acute respiratory distress syndrome (ARDS). Torque teno virus (TTV), from the Anelloviridae family, is proposed as a biomarker to measure the level of immunosuppression. Our objective was to describe the kinetics of TTV DNA loads and their association with critical illness-related complications.

Methods: We performed a longitudinal study in 115 patients with brain injury from a prospective cohort, collected endotracheal and blood samples at 3 successive time points after admission in the intensive care unit (ICU) (T1, 0-4 days post ICU admission; T2, 5-10; T3, 11-18), and measured viral DNA loads using the TTV R-GENE kit (BioMérieux) and a pan-Anelloviridae in-house quantitative real-time polymerase chain reaction.

Results: TTV DNA was detected in the blood of 69%, 71%, and 64% of patients with brain injury at T1, T2, and T3, respectively. Time-associated variations of TTV and anellovirus DNA loads were observed. Using a linear mixed-effects model, we found that HAP and ARDS were associated with lower blood anellovirus DNA loads.

Conclusions: Our results show that HAP or ARDS in patients who are critically ill is associated with changes in anellovirus DNA loads and should be evaluated further as a biomarker of immune disorders leading to these complications.