Recurrent bladder malakoplakia: A rare bladder lesion mimicking malignancy.

Background: Malakoplakia is a rare granulomatous disease that commonly involves the genitourinary tract with the urinary bladder being the most frequently affected site. It is characterized by histiocytes containing distinct basophilic calcified inclusions called Michaelis-Gutmann bodies. It is believed to result from abnormally functioning macrophages, with inclusions representing calcifications around incompletely digested bacteria. Although its pathogenesis remains unknown, it is well-documented that the condition is associated with chronic urinary tract infections and immunosuppression. Grossly, it can present as soft, yellow plaques, nodules, bladder mass, or even without any visible lesion. It poses a huge diagnostic challenge as it tends to mimic malignancy.

Case presentation: Described here is an 86-year-old female with recurrent bladder malakoplakia who presented with foul-smelling urine, hematuria, and dysuria. The clinicopathological features of this rare bladder lesion are described along with a review of the literature.

Conclusion: Early identification of malakoplakia's features by pathologists is essential for effective patient management. This condition should be considered in the differential diagnosis of bladder lesions, especially when Escherichia coli is present.