Purpose: Sepsis-induced immunosuppression is postulated to contribute to a heightened risk of nosocomial infection (NI). This prospective, single-center, observational study was conducted to assess whether low monocyte human leukocyte antigen-DR expression (mHLA-DR), proposed as a global biomarker of sepsis immunosuppression, was associated with an increased incidence of NI after septic shock.
Methods: The study included 209 septic shock patients. mHLA-DR was measured by flow cytometry at days (D) 3-4 and 6-9 after the onset of shock. After septic shock, patients were screened daily for NI at four sites (microbiologically documented pulmonary, urinary tract, bloodstream, and catheter-related infections). A competing risk approach was used to evaluate the impact of low mHLA-DR on the incidence of NI.
Results: At D3-4, we obtained measurements in 153 patients. Non-survivors (n = 51) exhibited lower mHLA-DR values expressed as means of fluorescence intensities than survivors (n = 102) (33 vs. 67; p < 0.001). The patients who developed NI (n = 37) exhibited lower mHLA-DR values than those without NI (n = 116) (39 vs. 65; p = 0.008). mHLA-DR ≤ 54 remained independently associated with NI occurrence after adjustment for clinical parameters (gender, simplified acute physiology score II, sepsis-related organ failure assessment, intubation, and central venous catheterization) with an adjusted hazards ratio (aHR) of 2.52 (95% CI 1.20-5.30); p = 0.02. Similarly, at D6-9, low mHLA-DR (≤ 57) remained independently associated with NI with an aHR of 2.18 (95% CI 1.04-4.59); p = 0.04.
Conclusions: In septic shock patients, after adjustment with usual clinical confounders (including ventilation and central venous catheterization), persistent low mHLA-DR expression remained independently associated with the development of secondary NI.