Prolonged suppression of monocytic human leukocyte antigen-DR expression correlates with mortality in pediatric septic patients in a pediatric tertiary Intensive Care Unit

Abstract

Introduction: Immunoparalysis is a syndrome with no clinical symptoms that occurs in some septic patients. Monocytic human leukocyte antigen-DR (mHLA-DR) expression has been used to identify patients in immunoparalysis and prolonged periods of reduced mHLA-DR expression have been correlated with a poor prognosis in sepsis. However, there is a lack of studies investigating mHLA-DR expression in pediatric septic patients.

Aim: To determine if mHLA-DR expression correlates with mortality in pediatric septic patients using the QuantiBRITE Anti HLA-DR/Anti-Monocyte,a Bechton Dickinson novel reagent that standardizes flow cytometry values.

Methods: We determined mHLA-DR expression in 30 patients with severe sepsis or septic shock admitted to the pediatric intensive care unit at Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil, between January 2013 and February 2015. mHLA-DR expression was quantified between days 3 to 5 and 5 to 7 after the onset of sepsis and the ΔmHLA-DR (mHLA-DR2 - mHLA-DR1) was calculated. We also measured mHLA-DR levels in 21 healthy control patients.

Results: Mean mHLA-DR expression was significantly lower in septic patients than in controls (P = .0001). Mortality was 46% in patients with negative ΔHLA-DR or <1000 mAb/cell and 7% in patients with positive ΔHLA-DR or >1000 mAb/cell. Mean ΔmHLA-DR levels were significantly different between survivors and non-survivors (P = .023).

Conclusion: ΔHLA-DR correlates with mortality in pediatric patients with septic shock or severe sepsis. This is the first study to have used the QuantiBRITE Anti HLA-DR/Anti-Monocyte reagent to quantify monocyte HLA-DR expression in pediatric septic patients.

Keywords: HLA-DR; immunoparalysis; monocytic HLA-DR; pediatric intensive care; sepsis; septic shock.