Dilated cardiomyopathy in children is most commonly due to which factors?

• A. Genetic mutation only
• B. Nutritional deficiency
• C. Viral infection or toxicity
• D. Bacterial infection

Answer: (C)

The main idea here is that viral myocarditis or toxin-related injury is the most common trigger for dilated cardiomyopathy in children. Viral infections, especially enteroviruses like Coxsackie and adenovirus, can inflame the heart muscle and cause lasting damage that leads to dilation of the ventricles and impaired pumping ability. Toxic exposures, such as certain chemotherapy agents (for example, anthracyclines), can injure myocardial cells and similarly result in a dilated, poorly functioning heart. Genetic mutations do contribute to pediatric dilated cardiomyopathy, but they are not the most frequent cause across cases. Nutritional deficiencies and bacterial infections are less commonly the underlying drivers of primary dilated cardiomyopathy in children.