Microbiology: Protozoa flashcards

67 %
33 %
Information about Microbiology: Protozoa flashcards

Published on February 25, 2014

Author: ExamMasters

Source: slideshare.net


Microbiology cards covering protozoa! Excellent for medical, nursing, college, and university students!

Unicellular organisms

Intestinal Protozoa  Amoeba: Entamoeba histolytica  Flagellates: Giardia lamblia & Trichomonas parvum/hominis  Ciliates: Balantidum coli  Sporozoa:  Isospora belli  Cyclospora cayetanensis  Cryptosporidium parvum/hominis  Sarcocystis hominis

Entamoeba histolytica Amoebiasis  World wide distribution – 3rd after malaria and     schistosomiasis Hand-mouth; fecal-oral; sexual transmission Increasing in homosexuals Resistant to chlorine Major complications: amoebic abscesses in liver, brain, lung  Amoebic pericarditis (rare) is most dangerous complication of amoebic liver abscess

Clinical Classification of Amoebiasis  Asymptomatic infection  Colonization without invasion  Symptomatic infection  Invasion with mild symptoms  Intestinal disease  Dysentery, colitis, amoeba  Extraintestinal amoebiasis  Liver, skin, lung, pleura, brain

Pathogenesis of Amoebiasis  Ingested cysts  trophozoites in large intestine 75% remain in lumen 15% invasive disease; adherence/digestion of epithelium; formation of flask-shaped ulcers  bacterial superinfection may occur  dissemination  liver abscess  rupture  pericardial disease

Clinical Presentation of Amoebiasis  Asymptomatic  Mild GI discomfort  Diarrhea, pain, blood, mucus  Weight loss  Organ specific symptoms  Dx: history, cysts/trophozoites, ELISA/PCR

Intestinal Flagellates  Giardia lamblia  Giardia intestinalis  Giardia duodenalis  Trichomonas hominis  Epidemiology: worldwide  Traveler’s/backpacker’s diarrhea: hikers/campers  Day care centers  Zoonotic; water, food (fecal-oral)

Life Cycle of Giardia  Ingestion of cysts  trophozoites attach to duodenal brush border causing irritation and obstruction of absorption  cysts in colon; passed in feces  See them moving in stool

Clinical Presentation of Giardia  Watery diarrhea, abdominal cramps  Weight loss  No blood, no pus, no fever  Steatorrhea – fatty and foul-smelling  Lactose intolerance  Antibody deficiency  Dx: fecal cysts/trophozoites; enterotest; ELISA; duodenal aspiration

Comparison of Clinical Presentations Amoebiasis Giardiasis  Asymptomatic  Non-inflammatory watery  Mild GI discomfort   Inflammatory     Diarrhea, pain, blood, mucu s Weight loss, fever Organ specific symptoms Dx: history, cysts/trophozoites, E LISA/PCR History: international travel       diarrhea, abdominal cramps Steatorrhea – fatty and foulsmelling No blood, no pus, no fever Weight loss Lactose intolerance Antibody deficiency Dx: fecal cysts/trophozoites; enterotest; ELISA; duodenal aspiration History: Camping in Northern US wilderness; drink mountain water

Oral Flagellate  Trichomonas tenax

Intestinal Ciliate  Balantidum coli – Balantidiasis  The only ciliated protozoa!  Common parasite of animals  No extraintestinal spread  Easily treated, not very common  Seen in ppl who are around animals all the time  Farmers, zoo workers  Tx: tetracycline

Intestinal Sporozoa      Isospora belli Cyclospora cayetanesis water or produce Cryptosporidium parvum/hominis water and food Non-inflammatory diarrhea Infection by ingestion of oocyst  infection of intestinal epithelium  Sexual & asexual stages – sporogony/schizogony  Self-limiting in immunocompetent; Severe in AIDS or other immunocompromised individuals  Dx: acid-fast oocysts in stool & history

Urogenital Flagellate  Trichomonas vaginalis  Sexual transmission

Amoeboflagellates  Primary CNS pathogens  Naegleria fowleri  Enter thru olfactory neuroepithelium causing primary amoebic meningoencephalitis (PAM) in healthy ppl  Trophozoites in CSF and tissue  Acanthamoeba culbertsoni  Balamuthia mandrillaris  Acanthamoeba and Balamuthia enter thru lower respiratory tract or thru broken skin causing granulomatous amoebic encephalitis (GAE) in immunocompromised individuals  Trophozoites and cysts in tissue

Haemoflagellates  Trypanosoma & Leishmania  Insect borne  Found in blood, tissue, lymph and CSF  Amastigote and trypomastigote most imp forms

Trypanosomiasis  T. Gambiense  Tsetse fly; West Africa  T. Rhodesiense  Tsetse fly; East Africa  T. Cruzi  Reduviid bug, Americas

T. Cruzi – American trypanosomiasis  Chagas disease  Vector: reduviid bug (triatomine bug)  Zoonotic  South/Central America  Infection thru eyes or open cuts, transplacental, at parturition or breastfeeding, blood, uncooked or contaminated food  Patho: bug feces  infection of local tissue  ulceration & inflammation  spread  localization in mesenchymal tissues of heart, GI, esophagus, etc  markedly enlarged heart, esophagus, and megacolon  tachycardia, chest pain, ECG changes, constipation

Chagas’ Disease  Chagoma, Romana’s sign  Hepatosplenomegaly, lymphadenopathy  Myocarditis w/ CHF; Meningoencephalitis  Tx: nifurtimox, benznidazole

Leishmaniasis sand fly  Vector – Phlebotomine  3 forms  Leishmania tropica: dermal/cutaneous form  Leishmania brasiliensis: mucocutaneous form  Leishmania donovanii: visceral form     Most severe form (KALA AZAR) – 100% fatality if untreated Hypoalbuminemia; hypergammaglobulinemia Irregular fever, marked weight loss, anemia, hepatosplenomegaly Amastigotes in deep tissue – liver, spleen, bone marrow  Drug: Sodium stibogluconate

Visceral leishmaniasis  Patho: Parasite localization in macro of RES  PANCYTOPENIA  high output heart failure  myocarditis/pericarditis  Leishmania – HIV coinfection on the rise

Tissue Sporozoa  Plasmodium (blood & tissue)  Malaria; Vector: female anopheles mosquito  Babesia (blood)  Babesiosis; Vector: Ixodes scapularis  Ixodes also carries lyme disease and human granulocytic anaplasmosis  Toxoplasma gondii (tissue)  Toxoplasmosis; Vector: cat  Most commonly reported parasitic disease following heart transplantation  Two life cycles, two hosts: sexual (sporogony) – definitive host; Asexual (schizogony) – intermediate host


Plasmodium  P. falciparum, ovale, vivax, malariae

Parasite detection: HRP2 detection, parasite LDH ... Dipstick tests

Complications of Malaria  Parasitized RBCs adhere  fibrin thrombi  microinfarcts in brain, heart  CHF, encephalopathy  death  Phagocytosis by macro  macro hyperplasia  hepatosplenomegaly  nephrosis  death

Pathology of Malaria  Fever, anemia, jaundice  Hepatosplenomegaly, hepatorenal syndrome  Pulmonary edema, CHF  Blackwater fever – dark urine  Encephalopathy – cerebral malaria

Protection against Malaria  Absence of receptor (“duffy antigen” FyaFyb)  G6PD deficiency  HbS  Thal

Malaria hypnozoites  P. vivax & P. Ovale  Use primaquin against hypnozoites  Chloroquine against severe malaria  Quinine in severe parasitemia and resistant malaria  Metronidazole for amoebic liver abscesses  Also for giardiasis, trichomoniasis, dracunculis medinensis

Babesiosis  Similar to malaria; co-infection w/ Lyme disease; Ixodes scapularis  Fever, chills, sweating, myalgias, fatigue, hepatospleno megaly, hemolytic anemia

Toxoplasmosis  Infection  flu-like  latency  reactivation if pt becomes immunocompromised  myocarditis, pericarditis, CHF

Helminthology  Platyhelminthes  Cestodes – tapeworms Tx: Praziquantel, Niclosamide  Trematodes – flukes Tx: Praziquantel  Nemathelminthes (Nematodes)  Intestinal worms Tx: Mebendazole  Tissue worms - filaria

Trematodes  Hermaphroditic flukes  Mammals – definitive hosts  Snails – 1st intermediate hosts  Fish, crustacea, vegetable – 2nd intermediate hosts  Schistosomes  Mammals – definitive hosts  Snails intermediate hosts

Clinical Classification  Lung fluke  Paragonimus westermanii CRAB  Liver fluke  Clonorchis sinensis FISH  Fasciola hepatica PLANT/VEGETABLE  Intestinal fluke  Heterophyes heterophyes FISH  Fasciolopsis buski PLANT/VEGETBALE  Tx: Praziquantel for all trematodes

Schistosomiasis (blood fluke)  Direct skin penetration by cecariae  S. Mansoni – intestinal (side spine)  S. Japonicum – intestinal (no spine)  S. Hematobium – urinary (terminal spine)  Tx: Praziquantel  Picture:  Left, S. mansoni  Middle, S. Haematobium  Right, S. japonicum

Diphylobothrium Latum  Broad or fish tapeworm  Very big  From ingestion of larvae in RAW fish  Clinical:  Low serum B12, eosinophilia  Atrophic gastritis  Megaloblastic anemia  Dx: history, presentation, eggs in stool  Tx: Praziquantel, Niclosamide

Taeniasis  Beef tapeworm – T. Saginata  Ingestion of larvae in undercooked/raw beef  Pork tapeworm – T. Solium  Ingestion of eggs in undercooked/raw pork  Associated w/ heart problems  Dx – eggs/proglottids in human feces; adult in intestines  Tx: Praziquantel, Niclosamide

Nemathelminthes  Intestinal nematodes  Ascaris lumbricoides – Roundworm  Strongyloides stercoralis – Threadworm  Ancylostoma duodenale – Hookworm  Necator americanus – Hookworm  Enterobius vermicularis – Pinworm  Trichuris trichiura – Whipworm  Trichinella spiralis – Porkworm  Infections characterized by eosinophilia and high IgE levels; hygiene and lifestyle is important

Ascaris lumbricoides - Roundworm  One of the most common human infections worldwide  Patho:  Stage 1: “infective” eggs ingested  larval migration  cough, hemoptysis (bloody sputum), dyspnea, hemorrhagic pneumonia, asthma attacks, pulmonary infiltration, urticaria  Stage 2: adult in intestine  dependent on worm load  pain, distension, nausea, anorexia, malnutrition (growth stunting in children), intestinal obstruction  Stage 3: adult migration  acute pancreatitis or obstruction, biliary obstruction, jaundice, appendicitis, peritonitis  Dx: larvae in sputum; ova & parasites in stool  Tx: Mebendazole

Strongyloides stercoralis Threadworm  Direct skin penetration  2 distinct adult forms  Filariform (infective form): larvae penetrate intact skin initiating infection  enter circulatory system  lungs  penetrate alveolar spaces  reach small intestine  mature to adult female (not male)  produce uninfective larvae  autoinfection   Uninfective  infective in intestine and stool Uninfective  adults in soil or become infective  Rhabditiform (uninfective form)

Strongyloides Clinical Features  Acute disease:  Ground itch, cough, dyspnea, wheezing, fever, epigastric pain  Chronic disease:  Abdominal cramping, diarrhea, pain  Severe disease  Hyperinfection syndrome  Extraintestinal spread (CNS, etc)  **dissemination in AIDS pts**  Dx: larvae in stool, urine, duodenum, enterotest  Tx: Ivermectin

Enterobius Vermicularis - Pinworm  Common in US; children  Eggs on perianal folds  perianal itching  Pricking anal pain, restlessness, sleeplessness  Dx: see them around anus, eggs on scotch tape  Tx: pyrantel pamoate or mebendazole Enterobius vermicularis

Necator Americanus & Ancylostoma Duodenale – Hookworms  Worldwide distribution; Enter thru FEET  Clinical stages:  Cutaneous Stage: ground itch  Pulmonary Stage: pulmonary hemorrhage  Cough, wheezing, pneumonitis  Intestinal Stage: GI discomfort, blood loss

Hookworm Infection Complications  Protein losing enteropathy  Fe deficiency anemia  Tachycardia  Stillbirth  Poor physical development  Dx: history and eggs in stool  Tx: mebendazole + dietary supplements  Wear shoes!!

Trichuris Trichura - Whipworm  Fecal-oral transmission; rare  Clinical:  Light infection: asymptomatic  Moderate infection:  Discomfort, gas, diarrhea/constipation  Heavy infection   Distension, vomiting, diarrhea, weight loss **RECTAL PROLAPSE**  Dx: history & eggs in stool  Tx: mebendazole

Trichinella Spiralis - Porkworm  No eggs  No external phase  Dead end transmission! – ingestion of undercooked meat  larvae turn to adults in intestinal cells  migrate to muscle  encyst

Clinical Presentation of Trichinella Spiralis     Diarrhea, constipation Fever, myalgia, fatigue Macular or petechial rash Periorbital edema, conjunctivitis/retinal hemmorrhage  Splinter hemmorhage; heart problems  Dx: muscle biopsy, positive serology, presentation symptoms  Tx: Thiabendazole – before tissue invasion  Rest + analgesics for after invasion

Tissue Nematodes = Filaria  Adults in tissue  Eggs not produced; microfilaria produced  Wuchereria bancrofti – mosquito  Brugia malayi/timori – mosquito  Loa loa – deer fly  Onchocerca volvulus – simulium black fly  Dracunculus medinensis – Cyclops (water flea)

Elephantiasis/Lymphatic filariasis  Wuchereria bancrofti  Brugia malayi & Brugia timori  Patho: microfilaria  adult worms in lymphatics  more microfilariae  lymphoedema  inflammatory reaction  elephantiasis  Early: acute inflammation, hypereosinophilia, massive lymphatic dilatation, bacterial and fungal infections, infection by wolbachia bacteria (tx: tetracycline)  Late: lymphoedema/elephantiasis; chyluria (lymph in urine)  Tx: DEC + Albendazole or Albendazole + Ivermectin

Elephantiasis  Dx: presentation, very high increase in eosinophils, IgE, IgG4, and specific antifilarial Ab; microfilariae in blood (nocturnal periodicity)  Sheath = pathogenic; no sheath = nonpathogenic

Onchocerca Volvulus  River blindness/onchocerciasis  Vector: Simulium Black Fly  Larvae in subcutaneous tissue  Patho: adult in onchocercoma  millions of migrating microfilariae  death due to immune response  onchodermatitis/keratitis  Dx: Skin biopsy nodules  tons of little worms  Tx: DEC or Ivermection (single dose)

Dracunculiasis  Dog, horse, cow, monkey  Vector: Cyclops (Water Flea)  Debilitatin skin eruptions  worms come out of them!!  Tx: metronidazole/thiabendazole Dracunculus medinensis

RELATED PRODUCTS If you enjoyed this presentation, please take a look at the rest of our products. Our website has many more FREE excellent presentations and tons of other FREE information. HIGHSCORE: Must Know Pharmacology Description: This is a book of 400+ flashcards covering 20 highly tested, and high-yield topics in pharmacology. It is designed so that you can use it anywhere on any device or print it out and use as flashcards. Get the eBook: HERE! Our site: Exam Masters Tutoring Service

RELATED PRODUCTS HIGHSCORE: Comparisons of High Yield Topics for the Medical Boards Description: This book contains over 100 comparisons of some of the most highly tested diseases and topics on the USMLE Step 2 CK. The questions on the exam are much more vague than what you see in the practice question banks and it is very difficult to differentiate between two diseases with similar symptoms. So this book is designed to help students improve their score by targeting these types of difficult questions. Get the Free Sample: HERE! Get the whole eBook: HERE! Other Products: HERE!

Add a comment

Related presentations

Related pages

Microbiology - Chapter 12 - Protozoa Flashcards | Quizlet

Start studying Microbiology - Chapter 12 - Protozoa. Learn vocabularly, terms, and more with flashcards, games, and other study tools.
Read more

Microbiology - Protozoa Flashcards | Quizlet

Start studying Microbiology - Protozoa. Learn vocabularly, terms, and more with flashcards, games, and other study tools.
Read more

Microbiology Medically Important Protozoa Flashcards ...

Study Flashcards On Microbiology Medically Important Protozoa at Cram.com. Quickly memorize the terms, phrases and much more. Cram.com makes it easy to get ...
Read more

Microbiology Protozoa Flashcards - Create, Study and Share ...

Toxoplasmosis gondii (from TORCH) Causes chorioretinitis, hydrocephalus and intracranial califications in congenital toxoplasmosis Causes encephalopathy in ...
Read more

Microbiology - Protozoan Flashcards - Cram.com

Study Flashcards On Microbiology - Protozoan at Cram.com. Quickly memorize the terms, phrases and much more. Cram.com makes it easy to get the grade you want!
Read more

microbiology- protozoans Flashcards

This Mastigophoran causes vaginitis and is the 2nd most prevalent STD in the US.
Read more

Microbiology Flash Cards

Microbiology flash cards. Biologists studying organisms on the microscopic scale will find these scientific flash cards helpful. ... What are protozoa?
Read more

Flashcards - Microbiology - scribd.com

Flashcards - Microbiology - Download as Word Doc (.doc / .docx), PDF File (.pdf), Text File (.txt) or read online.
Read more

Parasitology- Protozoa Flashcards - Course Hero

Vocabulary for Parasitology- Protozoa . Find, create, and access flashcards with Course Hero.
Read more