Malakoplakia of the urinary system.

Malakoplakia is regarded as a chronic granulomatous inflammatory disease with a good prognosis. It usually affects the urinary system, especially the urinary bladder. Bacterial infections, including E. coli are thought to be the main factor in pathogenesis. It frequently coexists with chronic diseases and immunosuppression state. Histopathological examination of affected tissue samples is thought to be the best diagnostic method. The basic microscopic feature is mixed inflammatory infiltration containing foamy histiocytes known as von Hansemann cells, frequently with basophilic inclusions known as Michaelis-Gutmann bodies. Symptoms and the clinical course of malakoplakia depend on location and the extent of the lesions. The lesion is treated successfully with antibiotic therapy and surgical excision.