von Hansemann Cells from Fresh Urine Sediment Samples in the Diagnosis of Malakoplakia.

Background: Malakoplakia is characterized by the presence of plaques with macrophages containing inclusion bodies. The diagnosis of this disease is carried out by biopsy of the lesion. The objective of this paper was to assess the value of fresh urine sediment in the diagnosis of malakoplakia.

Materials And Methods: Five suspected cases of malakoplakia that showed macrophages with inclusions called bodies of Michaelis-Gutmann (von Hansemann cells) in unstained urine sediment were processed with Papanicolaou, Giemsa, and periodic acid-Schiff (PAS) stains. Four of the five patients had a history of cystitis and had developed antibiotic resistance. The other patient had the characteristics cells in a routine urinalysis.

Results: Papanicolaou stain revealed intracytoplasmic eosinophilic or basophilic bodies, single or multiple in macrophages. Such bodies were stained deep red with PAS technique. Giemsa stain showed these bodies with a faint basophilic coloration, sometimes with a central core. Bladder biopsies established the definitive diagnosis, showing bodies within and outside macrophages, with a concentric "birds-eye" or "owl-eye" (targetoid) appearance.

Conclusions: Finding of von Hansemann cells in fresh urine sediment of patients with cystitis and a history of resistance to antibiotic scan leads to the diagnosis of malakoplakia. Giemsa stain can show in some cases the characteristic central core of Michaelis-Gutmann bodies. Malakoplakia is probably the result of an acquired defect in macrophage function causing impairment of bactericidal activity. A correct diagnosis is important because the spread to ureters with bilateral stenosis and obstruction can lead to kidney failure.