FDG-Avid Malakoplakia of the Ureter Mimicking Malignancy

Malacoplakia is a rare chronic granulomatous disease and frequently associated with Escherichia coli infection. We describe the contrast-enhanced CT and FDG PET/CT findings in a case of bladder and ureteral malakoplakia with E. coli urinary tract infection. Contrast-enhanced CT showed multiple enhancing mural nodules in the bladder and left ureter, ranging from several millimeters to 3.1 cm. The ureteral nodules showed significantly increased FDG uptake with SUVmax of 20.4, due to histiocyte, lymphocyte, and plasma cell infiltrates revealed by histopathology.