Abstract O-58: KINETIC OF MONOCYTIC HLA-DR EXPRESSION AFTER SEVERE PAEDIATRIC TRAUMA

Abstract

Aims & Objectives: In adults, major trauma induces immune dysfunction, with diminished expression of human leukocyte antigen DR expression on circulating monocytes (mHLA-DR). No paediatric data are available. This study described the kinetic of mHLA-DR expression following major paediatric trauma and the relationship between mHLA-DR and outcomes. Methods This was a prospective observational study of children with severe brain trauma (GCS<8 or Injury Severity Score ≥16) admitted to the Paediatric Intensive Care (PICU) or Trauma (TU) units in Red Cross War Memorial Children’s Hospital, Cape Town, South Africa, between November 2016 and March 2017. Blood samples for standardized mHLA-DR measurement were collected at Day 1, Day 3 and Day 8 after injury. Results Thirty-six children were included with 83 mHLA-DR measurements (Table 1). One patient withdrew after initial enrollment. mHLA-DR was lower in patients admitted to PICU compared to TU (p< 0.001). Overall, mHLA-DR nadir was at Day-1 and increased at Day-3 (p<0.001). mHLA-DR expression at Day-3 was significantly lower if inotropes were used (p=0.02) and if patients received red cell transfusion (p=0.006). mHLA-DR at Day 3 was higher in patients discharged at home at Day 30, compared to children still hospitalized or in rehabilitation at Day 30 (Table 1). In this cohort, mHLA-DR measurement was not correlated with the occurrence of secondary infection.Conclusions As in adults, mHLA-DR decreased rapidly after severe trauma in children and may be a marker of injury severity. Further research is recommended to determine the utility of mHLA-DR at Day 3 for predicting outcome.