Medicine The MOST severe complication of idiopathic hyper-eosinophilic syndrome is: A Endocardial fibrosis B Eosinophilic gastroenteritis C Interstitial pneumonia D Bone marrow failure 💡 Explanation The MOST severe complication of idiopathic hyper-eosinophilic syndrome is: ✓ Correct Answer: A. Endocardial fibrosis