Abstract
Introduction: Hypereosinophilic syndrome is a rare condition characterised by a high number of blood eosinophils, accompanied by tissue infiltration and associated symptoms. Currently, this term is reserved solely for idiopathic cases; however, it is a diagnosis of exclusion that requires the prior ruling out of a large number of conditions, with particular emphasis on haematological neoplasms. Case report: We present a patient who presented with mild ascites, accompanied only by hypereosinophilia, in whom a pleural effusion and concomitant pericarditis were subsequently discovered. A screening process was carried out to identify conditions presenting with these characteristics, and the patient was ultimately diagnosed with hypereosinophilic syndrome, showing a rapid response to corticosteroid treatment. Discussion: This case illustrates the variability of symptoms associated with this condition, not identifying similar cases to the one presented, alongside the extensive differential diagnosis required to diagnose this syndrome.
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