Evaluation of serum tenascin-c and osteopontin levels in pediatric patients with multisystem inflammatory syndrome in children (MIS-C): prediction of cardiac involvement and its relationship with progression

Multisystem Inflammatory Syndrome in Children (MIS-C), which emerges following COVID-19 infection, is a newly identified syndrome characterized by severe cardiac and systemic inflammatory symptoms in children. Understanding the pathophysiology of this disease, particularly the evaluation of biomarkers associated with disease severity and cardiac involvement, is crucial. The aim of this study is to assess serum Tenascin-C (TNC) and Osteopontin (OPN) levels in MIS-C patients, and to investigate the role of these biomarkers in predicting disease severity and cardiac involvement, as well as their impact on diagnostic and therapeutic processes. The study included 56 MIS-C patients and 20 healthy controls. Patients were divided into mild-moderate MIS-C and severe MIS-C groups, as well as those with and without cardiac involvement. Demographic characteristics, anthropometric measurements, vital signs, clinical symptoms, and system involvement were evaluated. Hemogram, biochemical, coagulation, and cardiac parameters were measured, along with serum TNC and OPN levels. Electrocardiographic (ECG) and echocardiographic (ECHO) assessments were also performed. In this study, it was found that patients in the severe MIS-C group had a longer duration of fever, and oral mucosal changes, respiratory distress, and hypotension were more frequently observed compared to the mild-moderate group (p<0.05). Among patients with cardiac involvement, fever duration was longer, conjunctivitis was more frequent, and lymphadenopathy was less common (p<0.05). The most frequently involved system was the hematologic system, and dermatologic and cardiac involvement were more prevalent in the severe MIS-C group (p<0.05). Among hemogram parameters, thrombocytopenia and lymphopenia were more common in the severe group (p<0.05), while biochemical findings showed elevated AST and lipase levels, decreased sodium levels (p<0.05), and more frequent occurrences of hyponatremia and hypoalbuminemia in the severe group (p<0.05). Procalcitonin levels were higher in the severe group (p=0.01). Cardiac parameters, including NT-proBNP, troponin, and CK-MB, were significantly higher in both the severe group and in patients with cardiac involvement (p<0.05). Although TNC and OPN levels were higher in the MIS-C group compared to the control group, and in the group with cardiac involvement compared to the group without cardiac involvement, no significant difference was found (p>0.05). However, TNC levels were significantly higher in the severe MIS-C group compared to the mild-moderate group (p<0.05). ROC analysis revealed that at a cutoff value of 1290.37 ng/L, TNC could distinguish severe cases with 61.5% sensitivity and 76.7% specificity. In conclusion, our study found that serum Tenascin-C levels were significantly associated with disease severity and could potentially serve as a biomarker for evaluating disease prognosis. Tenascin-C, when assessed alongside other inflammatory biomarkers in critical inflammatory diseases, may serve as a valuable tool to aid clinical decision-making.