Mortality in hypereosinophilic syndrome: 19 years of experience at Mayo Clinic with a review of the literature

Background: Information in the literature regarding causes of mortality in patients with hypereosinophilic syndrome (HES) is limited. Methods: This was a retrospective review of the morbidities and causes of death in HES patients at Mayo Clinic. Results: Overall, out of the 247 diagnosed HES patients, 23 died during the 19 years that this review encompassed. The cause of death was identified in 15 patients (65%): cardiac dysfunction in 5 (33%), infection in 3 (20%), unrelated malignancy in 3 (20%), thromboembolic phenomena in 2 (13%), and vascular disease in 2 (13%). Conclusion: Targeted monitoring of the at-risk end organs, combined with early treatment, may have the ability to improve survival and reduce morbidity in HES patients.