Serum hsa-miR-21 expression and its clinical value in pediatric patients with fulminant myocarditis.

objectiveFulminant myocarditis (FM) is a distinct and rare form of myocarditis. This study probed hsa-miR-21 expression in FM pediatric patients and its clinical value.

methodsThis study enrolled 88 FM pediatric patients and 90 healthy children (normal controls), with serum sample hsa-miR-21 levels measured by RT-qPCR. FM children were categorized into the good and poor prognosis groups. Correlations of hsa-miR-21 expression with myocardial injury markers [cardiac troponin I (cTnI), creatine kinase isoenzyme (CK-MB)], and independent risk factors and predictive value of hsa-miR-21 expression for FM patients' poor prognoses were analyzed by Pearson's, logistic regression, and receiver operating characteristic (ROC) curve analyses.

resultsSerum hsa-miR-21 levels were elevated in FM children relative to the healthy controls and linked with poor prognoses. hsa-miR-21 levels positively correlated with myoglobin (MYO), B-type natriuretic peptide (BNP), cTnI, and CK-MB levels. Elevated hsa-miR-21, CK-MB, left ventricular ejection fraction, C-reactive protein, lactate dehydrogenase, and lactate were independent risk factors for FM children's poor prognoses. Serum hsa-miR-21 levels yielded an area under the ROC curve of 0.790 in predicting FM pediatric patients' poor prognoses (58.1 % sensitivity, 87.7 % specificity), with positive and negative predictive values of 74.07 % and 81.97 %, respectively, demonstrating that hsa-miR-21 aided in predicting FM pediatric patients' poor prognoses to some extent.

conclusionSerum hsa-miR-21 was up-regulated in FM pediatric patients, and positively correlated with MYO, BNP, cTnI, and CK-MB. hsa-miR-21 expression was an independent risk factor for FM pediatric patients' poor prognosis, and predicted prognoses to some extent; however, the diagnostic accuracy was limited.