ABSTRACT
Objective:To explore the significance of plasma homocysteine (Hcy) as a new biomarker for the differential diagnosis of postural tachycardia syndrome (POTS) and suspected myocarditis in children.Methods:A total of 24 children diagnosed with POTS and 21 children diagnosed with suspected myocarditis treated in the Pediatrics Department of the Peking University First Hospital from July to December 2016 were included in the study.Plasma Hcy levels were measured in each subject and compared between children with POTS and suspected myocarditis.The receiver operating characteristic (ROC) curves were depicted for assessing the diagnostic potential of Hcy in distinguishing POTS from suspected myocarditis.Results:Plasma Hcy level in the POTS group was significantly higher than that in the suspected myocarditis group [(14.25±8.09) μmol/L vs.(8.99±3.19) μmol/L], which was also significantly higher than that of the mean levels in Beijing children [(8.82±5.58) μmol/L] (all P<0.05). When the cut-off was 9.36 μmol/L, the area under the ROC curve was 0.76, and the sensitivity and specificity for distinguishing POTS from suspected myocarditis were 71% and 68%, respectively. Conclusions:Plasma Hcy levels are helpful in the differential diagnosis of POTS and suspected myocarditis in children.