EOSINOPHILIC CYSTITIS AS THE FIRST MANIFESTATION OF HYPEREOSINOPHILIC SYNDROME

Abstract

<h3>Introduction</h3> Hypereosinophilic syndrome (HES) is a rare group of disorders defined by eosinophilia associated with end organ infiltration and damage. Eosinophilic cystitis (EC) is an inflammatory disorder marked by eosinophilic infiltration of the bladder wall. We describe a patient with dysuria and bladder mass secondary to idiopathic HES complicated by EC. <h3>Case Description</h3> Our patient is a 4-year-old male with history of asthma and allergic rhinitis presenting with suprapubic fullness associated with pain on urination. His lab work was notable for peripheral eosinophilia with absolute eosinophil count of 1720 which increased to 10640 cells/mcL. Ultrasound revealed a bladder mass, and biopsy found severe EC with more than 50% eosinophilic infiltration. The patient had isolated involvement of the bladder with no evidence of other organ damage. Viral and parasitic infections were ruled out as were myeloproliferative and lymphoproliferative disorders. He was diagnosed with idiopathic HES given the severe tissue hypereosinophilia on pathology with organ specific damage in the absence of primary HES and secondary causes of eosinophilia. Given prior travel history to Somalia and the degree of eosinophilia, the patient was empirically treated with praziquantel, which is an anti-parasitic medication. Treatment was then initiated with oral prednisone with good response. <h3>Discussion</h3> EC as a primary manifestation of HES is rare with few reported cases in the literature. HES should be considered in the differential of a patient who presents with either urinary symptoms or EC associated with peripheral eosinophilia.