Protozoa (Amoeba, Flagellates) PDF

PROTOZOA 13 AMOEBA, FLAGELLATES INTESTINAL AND ATRIAL PROTOZOANS They are single-celled organisms which are generally classified according to their organelles of locomotion Unicellular, eukaryotic organisms Animal-like protists No cell wall organelles: Nucleus NucleOLUs M...

PROTOZOA 13 AMOEBA, FLAGELLATES INTESTINAL AND ATRIAL PROTOZOANS They are single-celled organisms which are generally classified according to their organelles of locomotion Unicellular, eukaryotic organisms Animal-like protists No cell wall organelles: Nucleus NucleOLUs Mitochondria Locomotor Organelles Two regions of cytoplasm: ectoplasm (outer) endoplasm (inner) Contains at least one and some several nuclei Some contain vacuoles With special organs for locomotion  encystation TROPHOZOITE CYST Motile NON-MOTILE ACTIVE BUT NOT RESISTANT RESISTANT Transfer or Pathogenic stage infective stage Vegetative and Non-vegetative and reproductive non-reproductive excystation CLASSIFICATION BASED ON LOCOMOTORY ORGANELLES 1. SARCODINA/RHIZOPODA Organ: Pseudopodia Example: Amebae 2. MASTIGOPHORA/FLAGELLATA Organ: Flagella Example: FLAGELLATES 3. CILIOPHORA/CILIATA Organ: CILIA Example: BALANTIDIUM COLI 4. SPOROZOANS Organ: No definite locomotory organelle Example: PLASMODIUM, BABESIA CLASSIFICATION BASED ON TAXONOMY PHYLUM SARCOMASTIGOPHORA SUBPHYLUM MASTIGOPHORA SUBPHYLUM SARCODINA ATRIAL FLAGELLATES HEMOFLAGELLATES Acanthamoeba castellani Endolimax nana Chilomastix mesnili Entamoeba coli Dientamoeba fragilis Leishmania braziliensis Entamoeba dispar Giardia lamblia Leishmania donovani Entamoeba gingivalis Trichomonas hominis Leishmania tropica Entamoeba histolytica Trichomonas tenax Trypanosoma brucei Iodamoeba butschlii Trichomonas vaginalis Naegleria fowleri CLASSIFICATION BASED ON TAXONOMY PHYLUM APICOMPLEXA PHYLUM MICROSPORA Babesia spp. Encephalitozoon Cryptosporidium hominis Enterocytozoon Cyclospora cayetanensis Pleistophora Cystoisospora belli Nosema Plasmodium spp. Brachiola Toxoplasma gondi Vittaforma Trachipleistophora Microsporidium PHYLUM CILIOPHORA Balantidium coli CLASS SARCODINA Have protoplasmic processes, or pseudopodia, for locomotion Possess in their life cycle the: trophozoite stage precystic stage cystic stage metacystic stage With cystic stage except for Entamoeba gingivalis Inhabit the large intestine except for Entamoeba gingivalis Commensals except for Entamoeba histolytica  CYST NON-MOTILE Usually, infective Found in formed feces Resistant to damage Usually Smaller than trophozoite Best visualized using iodine  TROPHOZOITES MOTILE Usually not infective Found in liquid feces Susceptible to damage; easily disintegrates Usually larger than cyst Best seen using permanent stains AMOEBA INTESTINAL & EFFECT TO DEVELOPMENTA INFECTIVE MODE OF ATRIAL HABITAT HOST L STAGE TRANSMISSION AMOEBA STAGE ENTAMOEBA Pathogenic histolytica ENTAMOEBA coli Cyst & INGESTION/FECA COLON Trophozoite CYST L ORAL MOUTH ENDOLIMAX nana NON- IODAMOEBA Pathogenic butschlii ENTAMOEBA BUCCAL CAVITY TROPHOZOITE TROPH ORAL CONTACT gingivalis  INTESTINAL & SIZE NUMBER OF CHROMATOIDAL BODIES ATRIAL AMOEBA NUCLEI ENTAMOEBA histolytica 10-20 um 1-4 CIGAR OR BARR-SHAPED Splintered ends; ENTAMOEBA coli 10-35 UM 1-8 with broomstick appearance ENDOLIMAX nana 5-10 UM 4 Small spherical IODAMOEBA butschlii 5-20 UM 1 NO CHROMATOIDAL BODY; WITH LARGE GLYCOGEN MASS ENTAMOEBA gingivalis  INTESTINAL & SIZE KARYOSOME CYTOPLASMIC INCLUSIONS ATRIAL AMOEBA ENTAMOEBA histolytica 12-60 um CENTRAL, INDISTINCT INGESTED RBCS “BULL’S EYE KARYOSOME” ENTAMOEBA coli 15-50 um ECCENTRIC, OFF-CENTERED ENDOLIMAX nana 6-12 um IRREGULAR; BLOT-LIKE Bacteria, food vacuoles & SURROUNDED WITH debri IODAMOEBA butschlii 8-20 um ACHROMATIC GRANULES ENTAMOEBA gingivalis 10-20 um CENTRAL AND DISTINCT Food vacuoles and WBCS E. histolytica (Intestinal Amebiasis) 1. ACUTE/ASYMPTOMATIC ACUTE/SYMPTOMATIC bloody diarrhea, abdominal pain patient passes out TROPHOZOITES IN FECES 2. chronic/asymptomatic stool consistency is NORMAL patients are CARRIERS patient passes CYSTS IN FECES E. histolytica (Extraintestinal Amebiasis) trophozoite is TISSUE INVADING Forms: Hepatic amebiasis pulmonary amebiasis cerebral amebiasis  Extraintestinal Amoeba cyst trophozoite INTESTINAL & Important notes ATRIAL AMOEBA number trophozoite SIZE of nuclei Entamoeba currently regarded as the dispar 10-20 um morphologically similar to e. Bacteria; NO histolytica 4 RBCs Entamoeba 5-10 um previously regarded as the “small- hartmanni race e. histolytica” Entamoeba May appear like E. histolytica but is zoonotic infecting pigs & polecki monkeys  Facultative Amoeba 1. Naegleria fowleri cyst size: 7-15 um # of nucleus: 1 trophozoite: Measures 10-35 um 2 Forms: Amoeboid troph: lobophodia flagellated troph: 2 flagella Infective stage: amoeboid trophozoite Diagnostic stage: trophozoite in CSF & Brain Tissues; flagellated forms occasionally in CSF Cyst is NOT SEEN in brain tissues cyst has double wall Flagellated forms with 2 flagella and is RAPIDLY MOTILE  Facultative Amoeba 2. Acanthamoeba spp. cyst size: 10-25 um # of nucleus: 1 trophozoite: Measures 15-45 um With spine like projections: ACANTHOPODIA Infective stage: Infective stage: Cyst & trophozoite Diagnostic stages: Cyst and trophozoites in tissues; cyst has OUTER wrinkled wall Trophozoite has spine like process called ACANTHOPODIA; SLOWLY MOTILE  Facultative Amoeba 3. Balamuthia mandrillaris Isolated from soil and dust or from autopsy specimens of infected humans & animals Infective stages: cyst and trophozoite Can enter thru nasal passages ulcerated or broken skin Cyst & trophozoites in tissues cyst is 10-25 um with DOUBLE CYST WALL ATRIAL & LUMINAL FLAGELLATES  INTESTINAL HABITAT pathegenesis DEVELOPMENTAL INFECTIVE MODE OF STAGES STAGE TRANSMISSION Giardia lamblia small pathogenic intestine Chilomastix mesnili cyst & cyst Retortamonas trophozoite intestinalis non-pathogenic ingestion Enteromonas large hominis intestine Dientamoeba pathogenic or fragilis non-pathogenic trophozoite troph Pentatrichomonas non-pathogenic hominis  ATRIAL HABITAT pathegenesis DEVELOPMENTAL INFECTIVE MODE OF FLAGELLATES STAGES STAGE TRANSMISSION trichomonas tenax buccal non-pathogenic oral contact cavity troph troph trichomonas gut pathogenic sexual vaginalis contact  giardia lamblia cyst shape/size # of important notes nuclei ovoid 4 oblique axostyle 8-15um a pair of parabasal body trophozoite # of # of nuclei flagella motility important notes 8 (4 falling equipped with sucking disk 2 pairs) leaf-like resembles “old man with eyeglasses” kite-like bilaterally symmetrical  chilomastix mesnili cyst shape/size # of important notes nuclei lemon or curved fibril alongside nipple 1 of cytotosome 7-10um trophozoite # of # of nuclei flagella motility important notes 3 corkscre 1 external w, stiff, rotary, assumes shepherd’s 1 crook internal spiral jerky  enteromonas hominis cyst shape/size # of important notes nuclei resemble cysto of e. ellipsoidal 4 nana 6-8um nuclei in binucleate condition trophozoite # of nuclei # of flagella motility 1 3 anterior jerky slow 1 posterior directional  retortamonas intestinalis cyst shape/size # of important notes nuclei ovoid, fibrils extend above the pyriform 1 nucleus giving the “bird’s 4-7um beak” appearance trophozoite # of nuclei # of flagella motility 1 1 anterior rapid directional 1 posterior corkscrew Flagellates w/o cystic forms  DIENTAMOEBA FRAGILIS PREVIOUSLY CLASSIFIED AS AN AMOEBA TROPHOZOITE IS 5-15UM WITH HYALINE LEAF-LIKE PSEUDOPODIA KARYOSOME IS COMPOSED OF A CLUSTER OF 4- 8 GRANULES OFTEN REFERRED TO AS FRAGMENTED KARYOSOME OR TETRAKARYOSOME  GENUS TRICHOMONAS SIZES: PENTATRICHOMONAS HOMINIS: 5-15UM TRICHOMONAS TENAX: 5-12UM TRICHOMONAS VAGINALIS: 7-23 SHAPE: PYRIFORM EQUIPPED WITH UNDULATING MEMBRANE AND 5 FLAGELLA MOTILITY: FAST JERKY MOTILITY & TUMBLING MOTILITY AXOSTYLE EXTENDS BEYOND THE BODY TRICHOMONAS VAGINALIS IS THE ONLY PATHOGENIC AMONG THE SPECIES