Eosinophilia: Clinical experience from a tertiary care center in India

Eosinophilia is a prevalent laboratory abnormality that we encounter in day-to-day practice both in outpatient and inpatient settings. The causes range from primary to secondary spanning from an allergic response to clonal neoplastic proliferations. Identifying an etiology may be challenging in many cases and may sometimes require extensive evaluation. We aimed to find the clinical and etiological profile of patients with eosinophilia and the association of eosinophilia with end-organ involvement and IgE levels. The study was designed as a cross-sectional study over a period of two years (2019 to 2020). The study setting was outpatient and inpatient medical wards of a tertiary care center in north India. A detailed history and clinical examination were done on patients with eosinophilia detected in blood counts. Standard diagnostic protocols guided by positive clinical and diagnostic tests were followed to find etiologies in patients with eosinophilia. In our study, the most common cause overall and in each category of eosinophilia was parasitic infections (35%) followed by allergic disorders (29.3%). The most frequent symptoms were cough (32%), generalized weakness (25.5%), dyspnoea (24%), and a history suggestive of atopy (21%). On clinical examination, the most common finding was rhonchi or wheeze (24.5%). The most commonly affected end-organ was the lungs (13.2%) followed by the skin (4.7%). Parasitic infections are the most common cause of eosinophilia in our population. IgE levels correlate with a diagnosis of atopy or asthma and do not show a correlation with AEC. The lungs were the most frequently involved as end-organ in eosinophilia followed by the skin. We found no significant association between end-organ involvement and the degree of eosinophilia which highlights the importance of working up symptomatic patients for end-organ damage irrespective of the eosinophil count.