Malacoplakia is a rare inflammatory disorder of uncertain etiology. While most often involving the genitourinary tract it may also involve other sites, such as the gastrointestinal tract, gallbladder, lung, tongue, brain, lymph nodes, bone or skin.
Theories for the underlying cause of malacoplakia:
(1) defect in macrophage function with abnormal bacterial phagocytosis
(2) particular strain of bacteria resistant to digestion in phagosomes
