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Protozoa from Tissues Protozoa from tissues Leishmania spp. Naegleria fowleri Toxoplasma gondii Trichomonas vaginalis Trypanosoma spp. Leishmaniasis • Leishmania infantum, Leishmania donovani, … in macrophages of man. • Female sandflies: Phlebotomus spp., Lutzomia spp.,... • Cutanous, visceral leishmaniasis (Kala-azar). • Fever, hepatosplenomegaly, pancytopenia. • Serology - parasitological examination of bone marrow aspiration. (A. Van Gompel et al., T v G, 1997) Courtesy CDC Leishmania sp. Numerous ovoid to round small (2-6 μm) parasites in a bone marrow aspirate. In some parasites the typical rod shaped kinetoplast is seen beside the nucleus (May-Grünwald-Giemsa stain). Leishmania sp. Ovoid to round small (2-6 μm) parasites in a bone marrow aspirate. In the three parasites the typical rod shaped kinetoplast is seen beside the nucleus (May-Grünwald-Giemsa stain). Leishmania sp. Ovoid small (2-6 μm) intracellular parasite in a bone marrow aspirate. The typical rod shaped kinetoplast is seen beside the nucleus (May-Grünwald-Giemsa stain). Leishmania infantum Ovoid small (2-6 μm) parasites in a bone marrow aspirate. The typical rod shaped kinetoplast is seen beside the nucleus (May-Grünwald-Giemsa stain). Leishmania tropica Promastigotes (leptomonas) in rosettes in a culture of an orient sore on N.N.N. medium (Giemsa stain). Leishmania tropica Promastigotes (leptomonas) in rosettes in a culture of an orient sore on N.N.N. medium (Giemsa stain). Baghdad-boil, 2004 • Walter Reed Army Medical Center, Washington. • Several hundred US soldiers in Iraq. • Mostly cutaneous, but also visceral forms. Naegleria fowleri Typical ameboid trophozoites with one nucleus with a large central nucleolus (endosome) (Hematoxylin). Toxoplasma gondii • Coccidium of the cat (principal host). • Oocysts in contaminated food (eg. vegetables). • Cysts in meat (scheep, …) • Adenopathy. • Congenital disease. • Staining (MGG), culture, PCR. • Serology (IgG, IgM, IgA, …) Courtesy CDC Toxoplasma gondii In ascitic fluid of a mouse. Crescentic trophozoites. One end is more pointed than the other (Giemsa stain). Toxoplasma gondii These trophozoites from ascitic fluid of the mouse were made visible with immunofluorescence (Antiserum coupled with fluorescein isothiocyanate). Trichomonas vaginalis Several trophozoites mobile by flagella in a vaginal smear. They are slightly larger than the polymorphonuclear white blood cells (Unstained). Trichomonas vaginalis Trophozoite with flagella in a vaginal smear, slightly larger than polymorphonuclear white blood cells (Unstained). Trichomonas vaginalis Several trophozoites with one nucleus and flagella in a vaginal smear. They are slightly larger than the polymorphonuclear white blood cells (Gram stain). Trichomonas vaginalis Several trophozoites with one nucleus in a vaginal smear. They are slightly larger than the polymorphonuclear white blood cells (Gram stain). Trichomonas vaginalis In culture diluted with blood. Shown here are the short undulating membrane and the axostyle. Size 10 to 18µm (Osmium acid-Giemsa stain). African trypanosomiasis • West-Africa: Trypanosoma gambiense Glossina spp.- chronic “sleeping sickness”. • East-Africa: Trypanosoma rhodesiense Glossina spp. - high fever. • Diagnosis: thin and thick film, examination of CSF (parasites, IgM …), serology, ... Courtesy CDC Trypanosoma brucei gambiense Slender form, 30 μm long, with kinetoplast, central nucleus, undulating membrane and long free flagellum. This form is the usual in the smears of the peripheral blood of patients with sleeping sickness (May-Grünwald-Giemsa stain). Trypanosoma brucei gambiense Slender form, 30 μm long, with central nucleus, undulating membrane and long free flagellum. This form is the usual in the smears of the peripheral blood of patients with sleeping sickness (May-Grünwald-Giemsa stain). Trypanosoma brucei gambiense Long and short forms. The stumpy form is approximately 18 μm long and does not have a free flagellum (May-Grünwald-Giemsa stain). Courtesy CDC Trypanosoma cruzi • Chagas’ Disease in Central and South America. • Reduviid bug (Triatoma, ...) • Fever, heart, megacolon. • Diagnosis: thick and thin film, xenodiagnosis, serology ... Trypanosoma cruzi Small, plump trypanosome (20 μm) with a curved body and short, pointed rear end. Thick protruding kinetoplast (May-Grünwald-Giemsa stain). Trypanosoma cruzi Small, plump trypanosome (20 μm) with a curved body and short, pointed rear end. Thick protruding kinetoplast (May-Grünwald-Giemsa stain). Trypanosoma cruzi It is unusual to find these trypomastigotes in a thin blood smear. Shown here are the large protruding kinetoplast and the position in C- form (May-Grünwald-Giemsa stain). Trypanosoma cruzi In a thick blood film these trypanosomes also show their prominent kinetoplast and C-shape (Giemsa stain). Triatoma infestans South American “kissing bug” vector for Trypanosoma cruzi, the agent of Chagas disease. Courtesy CDC.
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