MR imaging findings of eosinophilic cystitis in an 8-year-old girl.

Eosinophilic cystitis is a rare inflammatory condition of the urinary bladder of unknown aetiology and characterized by eosinophilic infiltration of the bladder wall. We report the unique MR findings of eosinophilic cystitis in an 8-year-old girl who presented with peripheral eosinophilia. MR imaging revealed smooth and nearly circumferential thickening of the bladder wall showing distinct low signal intensity on T2-weighted images, which may histologically represent high cellularity due to massive eosinophilic infiltration.