ESPN 54th Annual Meeting

ESPN 2022


 
Hyponatremia, a low-cost diagnostic tool, that predicts severe cardiac involvement in children with MIS-C
KYRIAKI PAPADOPOULOU-LEGBELOU 1 MARIA KAVGA 1 EVANGELIA DESLI 1 PANAGIOTA KARANANOU 1 OLGA VAMBERTZI 1 SOFIA MARKIDOU 1 ELISSAVET VAKOUFTSI 1 PARASKEVI PANAGOPOULOU 1 EFIMIA PAPADOPOULOU-ALATAKI 1 MICHAIL PORTOKALAS 1 ATHANASIA NIKOLAKAKI 1 SOFIA CHANTAVARIDOU 1 MARIA FOTOULAKI 1 DESPOINA TRAMMA 1

1- ARISTOTELE UNIVERSITY OF THESSALONIKI
 
Introduction:

Objective: To highlight the role of low sodium in early recognition of severe cardiac involvement in children presenting with multisystem inflammatory syndrome (MIS-C).

Material and methods:

We describe a case series of nine patients, aged from 3,5 to 15,5 years that presented to our hospital during last winter and fulfilled the criteria of MIS-C with fever, elevated inflammatory markers and involvement of at least two organ systems, following a recent Covid-19 infection.

Results:

Eight out of 9 patients experienced gastrointestinal symptoms, 2/9 had lymphopenia, 3/9 thrombocytopenia and 2/9 children had severe hypoalbuminemia. Only one child developed decreased renal function, which was confirmed by high plasma urea and creatinine levels. However, hyponatremia (sodium:125-135mmol/L), was detected in 8/9 children (88.8%), which was severe in 3 children (33.3%). Severe hyponatremia was associated with severe cardiac involvement, as well as with remarkable high brain natriuretic peptide (BNP) values, combined with only a slight increase in troponin levels. Echocardiogram revealed mild left ventricular dysfunction (EF:50-55%) in 6/9 children, pericardial effusion (mild in 5/9, moderate in 2/9), and coronary artery dilation in 2/9 children. All patients were treated with intravenous human immunoglobin (IVIG), corticosteroids and low-dose of aspirin and only one child needed cardiac support with milrinone.

Conclusions:

Children with MIS-C often develop hyponatremia, the severity of which is related to the severity of the disease. Hyponatremia in MIS-C has been associated with inappropriate secretion of antidiuretic hormone, probably caused by the cytokine storm. Furthermore, high BNP levels in MIS-C patients, are mainly related to myocardial edema and not to myocardial cell damage, as observed in myocarditis, and to natriuresis, probably another underlying mechanism associated with hyponatremia.