Hypereosinophilic syndrome with multiorgan involvement: an interdisciplinary work-up.

A previously healthy 40-year-old man was referred to our emergency department with pruritic skin lesions and dyspnoea. Laboratory investigation revealed hypereosinophilia. Further diagnostic work-up confirmed the diagnosis of idiopathic hypereosinophilic syndrome (iHES), a rare myeloproliferative disease with a heterogeneous clinical presentation. We describe a unique case with cardiac, pulmonary, hepatic and cutaneous involvement at time of presentation. This case accentuates the importance of an extensive multidisciplinary diagnostic work-up, since iHES is a condition with potential rapid progressive multiorgan failure which requires prompt analysis and treatment. In addition, this case emphasises the importance of being aware of tunnel vision, especially during the COVID-19 pandemic, which might give rise to an increased risk of missing rare diagnoses. Our patient was treated with prednisolone, after which both his clinical condition and eosinophil concentrations markedly improved.