Hematologic parameters and biomarkers predictors of severity in Multisystem Inflammatory Syndrome in children associated with SARS-CoV-2

The multisystem inflammatory syndrome in children associated with SARS-CoV-2 (MIS-C) is characterized by a hyperinflammatory state resulting from a cytokine storm, evidenced by alterations in laboratory blood testing and acute-phase proteins. Objective: to describe the clinical and laboratory characteristics of patients hospitalized due to MIS-C and identify predictive markers of severity. Patients and Method: Retrospective study of 32 patients. The group was divided into critical and non-critical according to clinical presentation and therapy used. Clinical and laboratory aspects were studied, including complete blood count, coagulation tests, and biomarkers. Results: 18/32 were males, with a median age of 6.8 years. The most frequent manifestations were cardiovascular (84.3%), digestive (84%), and mucocutaneous (59%). The group of critical patients included 15 patients, 12 were males with a median age of 8.9 years, and the non-critical group included 17 patients, 6 were males with a median age of 5.4 years. The laboratory parameters at the admission in the global group showed increased C-reactive protein, D-dimer, leukocytes, neutrophils, ferritin, and fibrinogen. In contrast, albumin and blood sodium levels were decreased. At admission, the critical group was characterized by presenting thrombocytopenia, hypoalbuminemia, prolonged prothrombin time, and elevated ferritin. At the time of deterioration, there was an intensification of thrombocytopenia, increased C-reactive protein together with increased neutrophils level. Conclusion: The blood count, C-reactive protein, and albuminemia at admission proved to be significantly important in the identification of patients at risk of clinical deterioration.