Introduction
Hypereosinophilic syndrome (HES) is a rare group of disorders marked by sustained overproduction of eosinophils and eosinophil-mediated organ damage or dysfunction.1 Based on the underlying etiologies, HES is classified as primary (clonal), reactive, and idiopathic HES.2 The World Health Organization (WHO) has defined HES as a sustained increase in the absolute eosinophil count (AEC) above 1500/µL for longer than 6 months and tissue damage.3 Though the underlying pathophysiology remains unclear, clonal eosinophilic expansion and overproduction of eosinophilopoietic cytokines and their enhanced activity-mediated rise in eosinophils are the most accepted theories.2 Since the onset is usually insidious, the disease might remain obscured for a long period.3 Thus, it is extremely important to identify the subtle clinical features along with performing routine blood investigations for early diagnosis and management.3 Limited studies have presented the case details of the rare condition with eosinophil-mediated organ damage or dysfunction. The clinical and other features of the case presented in this study will contribute to expanding our understanding of this kind of rare health condition focusing on the resources-limited settings where tertiary care accessibility has several challenges. This case study aims to present an adult man, a case of secondary hyper eosinophilic syndrome in a tertiary care center in Nepal.
Keywords: Case Report, Hydropneumothorax, Peripheral eosinophilia, Secondary Hypereosinophilic Syndrome