Modern Pediatrics. Ukraine. (2026).2(154): 122-127. doi: 10.15574/SP.2026.2(154).122127
Mantak G. I., Andrikevych I. I., Shalamai M. O., Morozova I. V.
National Pirogov Мemorial Medical University, Vinnytsia, Ukraine

For citation: Mantak GI, Andrikevych II, Shalamai MO, Morozova IV. (2026). Clinical case of post influenza myocarditis in a child, modern aspects of diagnosing. Modern Pediatrics. Ukraine. 2(154): 122-127. doi: 10.15574/SP.2026.2(154).122127.
Article received: Dec 17, 2025. Accepted for publication: Mar 16, 2026.

Influenza virus is one of the most common respiratory pathogens that causes significant systemic complications, especially in children. Post-influenza myocarditis is not uncommon, yet remains a potentially life-threatening complication of influenza in pediatric practice. The problem of diagnosing and treating post-influenza myocarditis remains relevant due to the lack of clear algorithms for its detection in pediatric patients.
Aim – to analyze a clinical case of post-influenza myocarditis in a preschool child to improve the diagnosis of complications of influenza infection.
This case describes the course of post-influenza myocarditis in a 5-year-old patient hospitalized in the pediatric department due to increasing symptoms of severe respiratory infection. Initially, left-sided pneumonia was detected, which was complicated by the development of cardiovascular pathology. ECG showed the presence of metabolic changes in the myocardium, and Echocardiography (EchoCG) confirmed moderate mitral insufficiency with regurgitation and a decrease in the ejection fraction. Additionally, signs of hepatosplenomegaly were detected, indicating a systemic inflammatory response. Against the background of comprehensive treatment, which included antibacterial, antiviral, anti-inflammatory and cardiotropic therapy, a positive clinical trend was observed, including improvement of the clinical condition, normalization of laboratory parameters, increase in the ejection fraction.
Conclusions. The possibility of developing post-influenza myocarditis should be considered in children with severe influenza, especially in the presence of cardiovascular symptoms. Prospects for further research include the development of diagnostic algorithms for the early detection of cardiac complications of influenza in children.
The study was conducted in accordance with the principles of the Declaration of Helsinki. Informed consent was obtained from the child's parents for participate in the study.
The authors declare no conflict of interest.
Keywords: children, influenza infection, myocarditis.

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