Скачать презентацию Parasitology Protozoa l Are single celled animals Скачать презентацию Parasitology Protozoa l Are single celled animals

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Parasitology Parasitology

Protozoa l Are single celled animals l Trophozoites are motile l Cysts are involved Protozoa l Are single celled animals l Trophozoites are motile l Cysts are involved in transmission

GENERALITIES: l Parasites are organisms that obtain food and shelter by living on or GENERALITIES: l Parasites are organisms that obtain food and shelter by living on or within another organism. l The parasite derives all benefits from association and the host may either not be harmed or may suffer the consequences of this association, a parasite disease. l The parasite is termed obligate when it can live only in association with a host or it is classified as facultative when it can live both in or on a host as well as in a free form.

l Parasites which live inside the body are termed endoparasites whereas those which exist l Parasites which live inside the body are termed endoparasites whereas those which exist on the body surface are called ectoparasites. l Parasites that cause harm to the host are pathogenic parasites while those that benefit from the host without causing it any harm are known as commensals

What needs to be known? l Organism name ( scientific & common) l Morphology What needs to be known? l Organism name ( scientific & common) l Morphology (cyst, egg, larva, tophozoite, adult – M & F ) l Etiology l Epidemiology l Life Cycle l Symptoms, Pathology, Immunology l Diagnosis, Treatment & Prevention

INTESTINAL AND LUMINAL PROTOZOA l l l Organism that harbors the parasite and suffers INTESTINAL AND LUMINAL PROTOZOA l l l Organism that harbors the parasite and suffers a loss caused by the parasite is a host. The host in which the parasite lives its adult and sexual stage is the definitive host The host in which a parasite lives as the larval and asexual stage is the intermediate host. Other hosts that harbor the parasite and thus ensure continuity of the parasite's life cycle and act as additional sources of human infection are known as reservoir hosts. An organism (usually an insect) that is responsible for transmitting the parasitic infection is known as the vector.

Intestinal and luminal protozoa significant to human health include l Entamoeba histolytica (Amoebae) l Intestinal and luminal protozoa significant to human health include l Entamoeba histolytica (Amoebae) l Balantidium coli (Ciliates) l Giardia lamblia and Trichomonas vaginalis (Flagellates) l Cryptosporidium (Sporozoa) parvum and Isospora belli

Organism Symptoms Diagnosis Oro-fecal Dysentery with blood and necrotic tissue. Chronic: abscesses Stool: cysts Organism Symptoms Diagnosis Oro-fecal Dysentery with blood and necrotic tissue. Chronic: abscesses Stool: cysts with 1 -4 nuclei and/or trophs. Trophs in aspirate. GI: Iodoquinol or Metronidazole Abscess: Metronidazole Oro-fecal Fowl-smelling, bulky diarrhea; blood or necrotic tissue rare. Stool: typical old man giardia troph and/or cyst. Iodoquinol or Metronidazole. Balantidium coli Oro-fecal; zoonotic Dysentery with blood and necrotic tissue but no abscesses. Stool: ciliated trophs and/or cysts. Iodoquinol or Metronidazole. Cryptosporidium parvum Oro-fecal Diarrhea Ooocysts in stool Paromycin (investigational) Isospora belli Oro-fecal Giardiasis-like Ooocysts in stool Sulpha drugs Flagellate in Mebendazole; Entameba histolytica Giardia lamblia Transmission Vaginitis; Treatment

Entamoeba histolytica l Causes disease of the large intestine – amoebic dysentery – wherein Entamoeba histolytica l Causes disease of the large intestine – amoebic dysentery – wherein trophozoites feed on RBC causing ulcers. Also the liver and lung abscesses are possible l Naegleria – free-living amoeba in hot water sources. Causes primary amoebic meningoencephalitis ( PAM) l Acanthamoeba – free living amoebas

AMOEBIASIS (amoebic dysentery, amoebic hepatitis) Trophozoite: This form has an ameboid appearance and is AMOEBIASIS (amoebic dysentery, amoebic hepatitis) Trophozoite: This form has an ameboid appearance and is usually 15 -30 micrometers in diameter, although more invasive strains tend to be larger. The organism has a single nucleus with a distinctive small central karyosome. The fine granular endoplasm may contain ingested erythrocytes. The nuclear chromatin is evenly distributed along the periphery of the nucleus. l Cyst: Entameba histolytica cysts are spherical, with a refractile wall; the cytoplasm contains dark staining chromatoidal bodies and 1 to 4 nuclei with a central karyosome and evenly distributed peripheral chromatin l

l Flagellates l l l Giardia lamblia - a human parasite of the gastrointestinal l Flagellates l l l Giardia lamblia - a human parasite of the gastrointestinal tract. The organism is spread by direct contact or through contaminated food and water. Giardia spp. are pear-shaped, with hair-like flagella for motility. They cause the disease giardiasis (or lambliasis), an infection of the small intestine most common in tropical areas. Giardia spp. attaches by means of sucking discs to microvilli in the human intestine. Abdominal cramps, swelling, diarrhea and nausea may occur

Balantidium coli l This is a parasite primarily of cows, pigs and horses. The Balantidium coli l This is a parasite primarily of cows, pigs and horses. The organism is a large (100 x 60 micrometer) ciliate with a macro and a micro-nucleus. The infection occurs mostly in farm workers and other rural dwellers by ingestion of cysts in fecal material of farm animals. Man-to -man transmission is rare but possible. Metronidazole and iodoquinol are effective.

Trichomonas vaginalis l Trophozoite with undulating membrane and polar flagella l Presents with fishy-smelling Trichomonas vaginalis l Trophozoite with undulating membrane and polar flagella l Presents with fishy-smelling yellow discharge (guess where) l Males usually asymptomatic l Sexually transmitted

Organism Transmission Symptoms Diagnosis Treatment S. mansoni, skin S. japonicum penetration by cercaria Dermatitis, Organism Transmission Symptoms Diagnosis Treatment S. mansoni, skin S. japonicum penetration by cercaria Dermatitis, abdominal pain, bloody stool, periportal fibrosis, hepatosplenomegaly, ascites, CNS Eggs in stool Praziquantel Schistosoma skin hematobium penetration by cercaria Dermatitis, Eggs in urine urogenital cystitis, urethritis and bladder carcinoma Praziquantel Fasciolopsis Metacercaria buski on water chestnut Epigastric pain, nausea, diarrhea, edema, ascites Eggs in stool Praziquantel, C. sinensis, Cysts in fish O. felinus, or O. viverini Inflammation and Eggs in stool deformation of bile duct, hepatitis, anemia and edema Praziquantel Paragonimus Cyst in crab Cough (dry / rusty brown sputum),

Trematodes ( Flukes ) Schistosomes Trematodes ( Flukes ) Schistosomes

Schistosoma japonicum, mansoni Schistosoma japonicum, mansoni

Fasciolopsis buski ( Giant intestinal fluke) Fasciolopsis buski ( Giant intestinal fluke)

Paragonimus westermanii ( Lung fluke ) Paragonimus westermanii ( Lung fluke )

Clonorchis sinensis ( Chinese liver fluke ) Clonorchis sinensis ( Chinese liver fluke )

Echinococcus granulosus *(hydatid cyst) Echinococcus granulosus *(hydatid cyst)

Organism Transmissi Disease/ on symptoms Diagnosis Treatment Trypanosoma brucei Tsetse fly. Sleeping Hemoflagellate Blood Organism Transmissi Disease/ on symptoms Diagnosis Treatment Trypanosoma brucei Tsetse fly. Sleeping Hemoflagellate Blood stage: sickness; in blood or Suramin or cardiac failure. lymph node. petamidine isethionate; T. cruzi Reduvid (kissing) bug. Chagas Hemoflagellate CNS: disease: in blood or melarsoperol megacolon, tissue. Nifurtimox and cardiac failure. Benzonidazole. Leishmania donovani Sand fly Visceral leishmaniasis, granulomatous skin lesions. Intracellular Pentosam; (macrophages Pentamidine ) leishmanial isethionate. bodies. L. tropica Sand fly. Cutaneous lesions. As for L. donovani. L. braziliensis Sand fly Mucocutaneou As for L. s lesions. donovani. As for L. donovani.

l Trypanosoma – l flagellate with Tsetse fly as vector l Causes African sleeping l Trypanosoma – l flagellate with Tsetse fly as vector l Causes African sleeping sickness l Trypanosoma cruzii – l Chaga’s disease l kissing bug as vector l Leishmania – l Sandfly as vectors l Visceral, cutaneous & mucocutaneous lesions

Blood & Tissue Protozoans Blood & Tissue Protozoans

Organism Transmissi Disease/ on symptoms Diagnosis Plasmodium Female falciparum anopheline P. ovale, mosquito. P. Organism Transmissi Disease/ on symptoms Diagnosis Plasmodium Female falciparum anopheline P. ovale, mosquito. P. malariae and P. vivax Malarial Plasmodia in paroxysm: rbc, typical of chills, fever, the species headache, involved. nausea cycles. Babesia microti Tick Hemolytic anemia, Jaundice and fever Toxoplasma gondii Oral from cat Adult: flu like; Intracellular (in fecal material; congenital: macrophages) or meat abortion, tachyzoites. neonatal blindness and neuropathies. Pneumocystis Cough Pneumonia Treatment Quinine derivatives Proguanil Lariam Typical None; self organism resolving. (Maltese cross) in rbc. Pneumocystis Sulphonamide s, pyemethamine, possibly spiramycin (non-FDA). Trimethoprim and

Sporozoans l Cryptosporidium parvum – found in waters, a self limited diarrhea l Plasmodium Sporozoans l Cryptosporidium parvum – found in waters, a self limited diarrhea l Plasmodium species cause malaria l Anopheles mosquito as vectors l Complicated life cycle. l P. vivax, P. ovale, P. malariae, P. falciparum l Toxoplasma gondii – reservoir in cats l Human ingest cyst from cats feces or undercooked meat. Danger in fetus development

Malaria Malaria

Nematodes (Roundworms) Nematodes (Roundworms)

Organism Transmissi Symptoms on Diagnosis Treatment Ascaris Oro-fecal lumbricoides Abdominal pain, weight loss, distended Organism Transmissi Symptoms on Diagnosis Treatment Ascaris Oro-fecal lumbricoides Abdominal pain, weight loss, distended abdomen Stool: corticoid oval egg (4070 x 35 -50 μm) Mebendazole Trichinella spiralis Poorly cooked pork Depends on worm location and burden: gastroenteritis; edema, muscle pain, spasm; eosinophilia, tachycardia, fever, chill headache, vertigo, delirium, coma, etc. Medical history, eosinophilia, muscle biopsy, serology corticosteroid and Mebendazole Oro-fecal Abdominal pain, bloody diarrhea, prolapsed rectum Stool: lemonshaped egg (5055 x 20 -25μm) Mebendazole Peri-anal pruritus, rare abdominal pain, nausea Stool: embryonated eggs Pyrental pamoate (60 x 27 μm), flat or Mebendazole Trichuris trichiura Enterobius vermicularis Oro-fecal

Trichinella spiralis Trichinella spiralis

Trichuris trichiuria Trichuris trichiuria

Enterobius vermicularis Enterobius vermicularis

Strongyloides stercoralis (threadworm) Strongyloides stercoralis (threadworm)

Organism Transmissi Symptoms on Strongyloides Soil-skin, stercoralis autoinfection Necator Oro-fecal americanes; (egg); skin Ancylostoma Organism Transmissi Symptoms on Strongyloides Soil-skin, stercoralis autoinfection Necator Oro-fecal americanes; (egg); skin Ancylostoma penetration duodenale Diagnosis Treatment Itching at infection site, rash due to larval migration, verminous Stool: rhabditiform Ivermectin or pneumonia, midlarvae (250 x 20 Thiabendazole epigastric pain, 25μm) nausea, vomiting, bloody dysentery, weight loss and anemia Maculopapular erythema (ground itch), broncho. Stool: oval pneumonitis, segmented epigastric eggs (60 x 30 Mebendazole

Necator americanus (hookworm) Necator americanus (hookworm)

Dracunculus medinensis (Guinea worm) Dracunculus medinensis (Guinea worm)

Organism Dracunculus medinensis Transmissi Symptoms on Oral: cyclops in water Diagnosis Blistering skin, Physical Organism Dracunculus medinensis Transmissi Symptoms on Oral: cyclops in water Diagnosis Blistering skin, Physical irritation, examination inflammation Treatment Mebendazole Wuchereria bancrofti; W. brugia malayi Mosquito bite (elephantiasi s) Recurrent fever, lymphadenitis, splenomegaly, lymphedema, elephantiasis Medical history, physical examination, microfilaria in blood (night sample) Mebendazole; Diethylcarbamazine Onchocerca volvulus Nodular and erythematous dermal lesions, eosinophilia, urticaria, blindness Medical history, physical examination, microfilaria in nodular aspirate Mebendazole; Diethylcarbamazine Black fly bite

Toxocara canis & catii ( visceral larval migrans) Toxocara canis & catii ( visceral larval migrans)

Ancylostoma braziliensis ( cutaneous larva migrans, creeping eruption) Ancylostoma braziliensis ( cutaneous larva migrans, creeping eruption)

Organism Transmission Symptoms Diagnosis Treatment Cyst in beef Epigastric pain, vomiting, diarrhea Proglottids or Organism Transmission Symptoms Diagnosis Treatment Cyst in beef Epigastric pain, vomiting, diarrhea Proglottids or eggs in stool Praziquantel or perianal area Tenia solium Cyst in pork Epigastric pain, vomiting, diarrhea Proglottids or eggs in stool Praziquantel or perianal area Tenia saginata T. solium Oro-fecal Cysticercosis Muscle pain and weakness, ocular and neurologic Roentgenogr aphy, anticysticercal Praziquantel antibody (EIA)

Cestodes- (Tapesworms) Cestodes- (Tapesworms)

Taenia solium Taenia solium

Diphylobotrium latum Diphylobotrium latum

Organism D. latum Transmission Cyst in fish E. granulosus Oro-fecal E. Symptoms Diagnosis Treatment Organism D. latum Transmission Cyst in fish E. granulosus Oro-fecal E. Symptoms Diagnosis Treatment Abdominal pain, loss of weight, anorexia, malnutrition and B 12 deficiency problems Proglottids or eggs in stool Praziquantel or perianal area Large cysts produce various symptoms depending on the location of the organism. Roentgenogr aphy, antihydatid fluid antibody (EIA), Casoni skin test Surgery, formalin injection and drainage, Praziquantel Surgery,

Hymenolepsis nana ( dwarf tapeworm) Hymenolepsis nana ( dwarf tapeworm)