LAUSR

Entamoeba histolytica (EH) is a human protozoon that causes amoebiasis. This protozoon exists in two forms: the infective, nondividing cyst (10-15 μm in diameter), and the actively dividing, invasive trophozoite (12-50 μm in diameter). Upon ingestion by the host, the dormant, nonmotile cyst is converted to the actively dividing trophozoite in the colon. EH causes a range of disease manifestations, including dysentery, amoebic colitis, ameboma, and invasive disease and results in amoebic abscesses mainly in the liver and less frequently in the lung and the brain. Amoebic abscess occurs when EH trophozoites travel to extraintestinal tissues through the bloodstream. EH is usually acquired through ingestion of food or water contaminated with fecal cysts, although sexual transmission has also been reported, particularly via contact with commercial sex workers or in men who have sex with men, probably via the fecal-oral route. Genitourinary amoebiasis is an unusual from of presentation of this parasitosis, and bladder amoebiasis is a very uncommon clinical entity. Two major transmission routes have been postulated for genitourinary amoebiasis. One is a direct infection from the rupture of an infected liver abscess around the kidney, where the protozoan parasite passes through the pelvis and urinary bladder, respectively. The second transmission route is through blood circulation or the lymphatic system from the kidney and urinary system. Nevertheless, an “ascending route” where the protozoa located at the anorectal area can colonize the urethra (eg, in homosexuals) is also possible. This form of intercourse among men is the cause of penile amoebiasis presenting as genital ulceration. The first observation of EH in urine was made by Baelz in 1883, who found it in the blood-stained urine of a Japanese patient. Subsequently, successive cases of urinary amoebiasis have been reported in the medical literature. Interestingly, in one of them by Watson, a controversial discussion on the viability of EH under the toxic chemical properties of the urine is mentioned. Herein, we report the case of a 24-year-old male, sub-Saharan immigrant from Ghana, who went to the outpatient clinic suffering hematuria, dysuria, suprapubic pain and fever (38 C). The rest of the clinical examination was normal with absence of organomegalies and adenopathies. A sample of voided urine was sent to the laboratory for urinary sediment analysis, cytology and culture. In a wet mount of the urinary sediment obtained by centrifugation, some structures like parasitic cysts (with a round shape, refractile wall, presence of a nucleus inside, and an approximate size of 15 μm in diameter) were observed (Figure 1). These were very similar in morphology to E. histolytica/E. dispar species. In the cytocentrifuged cytological smear that was stained by the Papanicolaou method, its presence was observed, and its structure was compatible with an amoeba. It consisted of a welldefined greenish cytoplasm of irregular contours, like pseudopods, with some vacuoles phagocytizing red blood cells and a striking