PIMS-TS immunophenotype: description and comparison with healthy children, Kawasaki disease and severe viral and bacterial infections.

ABSTRACT

BACKGROUND: A new clinical syndrome named Paediatric Inflammatory Multisystem Syndrome Temporally Associated with SARS-CoV-2 (PIMS-TS) has been described. This new disease is a leading cause of hospital and paediatric intensive care unit (PICU). It has been related to immunity dysregulation. METHODS: Prospective-retrospective observational study to describe the innate cell signature and immunophenotype of children admitted to PICU because of PIMS-TS (from March 2020 to September 2020). The immunophenotype was done through the expression analysis of these proteins of mononuclear cells CD64, CD18, CD11a and CD11b. They were compared with previous healthy controls and children admitted to PICU because of bacterial infection, viral infection and Kawasaki disease (KD). Two hundred and forty-seven children were studied 183 healthy controls, 25 viral infections, 20 bacterial infections, 6 KD and 13 PIMS-TS. RESULTS: PIMT-TS showed the lowest percentage of lymphocytes and monocytes with higher relative numbers of CD4+ (p = .000). Monocytes and neutrophils in PIMS-TS showed higher levels of CD64 expression (p = .000). Also, CD11a and CD11b were highly expressed (p =,000). CONCLUSION: We observed a differential cell innate signature in PIMS-TS. These findings are consistent with a proinflammatory status (CD64 elevated expression) and lymphocyte trafficking to tissues (CD11a and CD11b). More studies should be carried out to confirm our results.