Malakoplakia of the Urinary Tract: A Benign Disease with a Possible Malignant Outcome

Abstract

Abstract:Introduction: Malakoplakia is a rare chronic inflammatory disease which commonly affects the urogenital tract. The exact pathogenesis is not fully understood, but some associated conditions which include immunodeficiency, malignancy or chronic bacterial infection, have been suggested. The definite diagnosis relies on identifying the Michaelis-Gutmann bodies microscopically. Case Report: A 62-year-old woman with poorly controlled diabetes mellitus presented with gross hematuria for a few months. Subsequent investigations showed a positive urine culture (Escherichia coli -E. coli), and flexible cystoscopy showed a 1 cm plaque-like lesion at the left posterior wall of the urinary bladder as well as several smaller, similar lesions noted at various different sites. Biopsy of the lesion showed a proliferation of macrophages (CD68+) with abundant, glandular cytoplasm and the presence of Michaelis-Gutmann bodies (PAS+, Von Kossa+), which was consistent with malakoplakia. Computed Tomography (CT) urogram showed no hydronephrosis, with good contrast excretion from both kidneys as well as satisfactory drainage down to the bladder. She was then treated with antibiotics, but still had on and off urinary tract infection. About a year later, she presented with urosepsis and acute renal failure, and was admitted to the urological ward. Urgent CT urogram showed bilateral hydronephrosis with both lower ureters distended with hyperdense contents (malakoplakia plaques). Emergency bilateral percutaneous nephrostomy (PCN) was performed. Her condition was stabilized with antibiotics, and her renal function improved with PCN drainage. Several treatment options were offered to the patient, but in view of her significant pre-morbid condition, she opted for bilateral long-term PCN. Conclusion: Malakoplakia was thought to be a treatable and relatively benign disease, but in some cases, it might result in renal failure due to bilateral ureteric involvement. Early diagnosis together with adequate antibiotic treatment is important in patients with malakoplakia, and they should be closely followed up to prevent future development of renal insufficiency.

Role of MDCT in Assessment of Inflammatory Renal Disease

“…These masses vary in size from a few millimetres to several centimetres. Occasionally, malacoplakia can be locally aggressive and invades surrounding structures even causing bone erosions (8) .…”