Malakoplakia

Malakoplakia (also spelled malacoplakia) is a rare chronic inflammatory condition characterized by the formation of soft, yellowish-brown plaques or nodules in affected tissues. The disease is thought to result from a defect in macrophage bactericidal activity, leading to an abnormal immune response to bacterial infections, most commonly Escherichia coli. The hallmark histological finding is the presence of Michaelis-Gutmann bodies — distinctive calcified, concentrically layered inclusions found within macrophages (known as von Hansemann cells) — which are considered pathognomonic for the condition. Malakoplakia most frequently affects the urinary tract, particularly the urinary bladder, but can also involve the kidneys, ureters, urethra, and other organs including the gastrointestinal tract, lungs, skin, bones, and retroperitoneum. Symptoms depend on the site of involvement and may include urinary frequency, hematuria, flank pain, recurrent urinary tract infections, and the presence of mass lesions that can mimic malignancy. The condition is more common in women and in individuals who are immunocompromised, including organ transplant recipients and those on immunosuppressive therapy. Treatment of malakoplakia focuses on addressing the underlying bacterial infection with antibiotics that achieve good intracellular penetration, such as fluoroquinolones or trimethoprim-sulfamethoxazole. Bethanechol, a cholinergic agonist, has been used to enhance intracellular bactericidal activity by increasing cyclic guanosine monophosphate (cGMP) levels in macrophages. Surgical intervention may be necessary for obstructive lesions or when malakoplakia mimics or coexists with malignancy. Reduction of immunosuppressive therapy, when feasible, is also an important component of management. Prognosis varies depending on the extent and location of disease, with renal parenchymal involvement carrying a more guarded outcome.

Inheritance

Sporadic

Usually appears on its own, not inherited from a parent

Age of Onset

Adult

Begins in adulthood (age 18 or older)

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Source: NORD Rare Disease Centers + NIH Undiagnosed Diseases Network (UDN) · centers verified active within last 12 months

Source: PubMed + NIH RePORTER + openFDA + clinical-journal RSS · last 30 days · disease-tagged at ingest by AI extraction with human QC

Common questions about Malakoplakia