Microbio - CHAPTER 23 REVIEW PDF

Chapter 23 – Protozoans 1. Amoebae a. What is the name of the organism? i. Entamoeba histolytica ii. Naegleria flowleri b. What is the route of infection? i. Entamoeba – ingestion; infection most commonly occurs by drinking...

Chapter 23 – Protozoans 1. Amoebae a. What is the name of the organism? i. Entamoeba histolytica ii. Naegleria flowleri b. What is the route of infection? i. Entamoeba – ingestion; infection most commonly occurs by drinking contaminated water ii. Naegleria fowleri – inhalation; infection occurs when swimmers inhale contaminated water c. Signs and symptoms? i. Entamoeba histolytica carried asymptomatically in the digestive tracts of humans 1. Invasive amebic dysentery: severe diarrhea, colitis, appendicitis, and ulceration of the intestinal mucosa d. Prognosis? i. Entamoeba: amebic dysentery and invasive extraintestinal amebiasis can be fatal ii. Naegleria fowleri: causes hemorrhage, coma, and usually death within 10 days;– death e. Vector? i. Entamoeba: water ii. Naegleria fowleri: protozoan infects the nasal mucosa from swimming water, penetrates the brain, and feeds on brain tissues; contaminated water f. Anything really creepy? i. Entamoeba: Few cause disease; Excystment occurs in the small intestine; Trophozoites migrate to the large intestine ii. Naegleria fowleri: 2006-2015 – 37 infections 2. Flagellates – Trypanasoma cruzi a. What is the name of the organism? i. Trypanosoma cruzi – Chagas’ disease b. What is the route of infection? i. Bites – bit of insects in genus Triatoma c. Signs and symptoms? i. Acute stage characterized by chagomas (swelling at bites) ii. Generalized stage with fever, swollen lymph nodes, myocarditis, and enlargement of spleen, esophagus, and colon iii. An asymptomatic chronic stage iv. Symptomatic stage characterized by congestive heart failure following formation of pseudocysts d. Prognosis? i. Parasite-induced heart disease is a leading cause of death in Latin America e. Vector?  i. Triatoma insects ii. Primary reservoirs: opossums and armadillos f. Anything really creepy? i. “Kissing bugs” feed preferentially from blood vessels in the lips 3. Flagellates – Trypanosoma brucei gambiense (African sleeping sickness) a. What is the name of the organism? i. Trypanosoma brucei gambiense b. What is the route of infection? i. Bite – fly bite becomes a lesion with dead tissue c. Signs and symptoms i. Parasites in the blood trigger fever, lymph node swelling, and headaches ii. Meningoencephalitis d. Prognosis? i. Death in months e. Vector? i. Tsetse fly f. Anything really creepy? i. Antigenic variation makes vaccine difficult (100 varieties) ii. T. brucei matures in the salivary gland of the tsetse fly; tsetse flies directly inject T. brucei; T. brucei live outside hosts’ cells 4. Flagellates – Leishmania a. What is the name of the organism? i. Leishmania b. What is the route of infection? i. Originates from a bite c. Signs and symptoms? i. Cutaneous leishmaniasis: large painless skin ulcers form at the bite wounds ii. Mucocutaneous leishmaniasis: skin lesions enlarge to encompass mucous membranes of the mouth, nose, or soft plate iii. Visceral leishmaniasis: macrophages carry the parasite to the liver, spleen, bone marrow, and lymph nodes d. Prognosis? i. Fatal in 95% of untreated cases of visceral e. Vector? i. Phlebotomus or Lutzomyia (sand fly) f. Anything really creepy? i. 5. Apicomplexan – Giardia a. What is the name of the organism? i. Giardia intestinalis – causes giardiasis b. What is the route of infection? i. Ingestion – ingest cysts in contaminated food, water, or hands c. Signs and symptoms? i. Diarrhea, pain, bloating, nausea, vomiting, and fever  d. Prognosis? i. Ranges from asymptomatic infection to gastrointestinal disease e. Vector? i. Beavers are a common reservoir ii. Cyst from food, water, or hands f. Anything really creepy? i. Hydrogen sulfide detected in the breath or stools 6. Apicomplexan – Trichomonas a. What is the name of the organism? i. Trichomonas vaginalis b. What is the route of infection? i. Sexual encounters c. Signs and symptoms? i. Women: vaginosis – causes odorous discharge, vaginal and cervical lesions, abdominal pain, and painful urination and intercourse d. Prognosis? i. Treated with nitroimidazole drugs ii. Vaginosis in women iii. Asymptomatic in men e. Vector? i. Humans f. Anything really creepy? i. Most common protozoan causing disease in industrialized nations 7. Apicomplexans – Plasmodium (causes malaria) a. What is the name of the organism? i. Plasmodium vivax ii. Plasmodium falciparum b. What is the route of infection? i. Bite from anopheles’ mosquito c. Signs and symptoms? i. Plasmodium vivax: mildest and most prevalent form; dormant in the liver; fever every 2 days ii. Plasmodium ovale and Plasmodium malariae: benign; restricted geographically iii. Plasmodium falciparum: (most deadly); severe anemia; 50% morality; blood cells develop knobs that block capillaries; affects the kidneys, liver, and brain; black urine is characteristic d. Prognosis? i. P. falciparum: death of brain tissue can be fatal within 24 hours e. Vector? i. Anopheles’ mosquito f. Anything really creepy? i. Black urine 8. Apicomplexans – Toxoplasma  a. What is the name of the organism? i. Toxoplasma – T. gondii is the causative agent of toxoplasmosis b. What is the route of infection? i. Infection due to consumption of undercooked meat containing the parasite ii. Ingestion or inhalation of contaminated soil can also occur iii. Cats are definitive host c. Signs and symptoms? i. May alter human behavior – infected men tend to be introverted, suspicious and rebellious, whereas infected women tend to be extraverted, trusting and obedient d. Prognosis? i. Chronic condition by forming cyst with bradyzoites e. Vector? i. Cat fluids f. Anything really creepy? i. Most severe in AIDS patients and fetuses ii. Transplacental transfer of the protozoan can cause abortion, stillbirth, and various birth defects 9. Helminths – Cestodes a. What is the name of the organism? i. Cestodes – tapeworms b. What is the route of infection? i. Ingestion: uncooked meat c. Signs and symptoms? i. Taenia Solium is pork tapeworm can cause cystercosis (encystment in various tissues) d. Prognosis? i. Most individuals shed strobila without having symptoms, intestinal blockage can occur e. Vector? i. Cattle and swine serve as intermediate hosts f. Anything really creepy? i. Diphyllobthrium latum (fish tapeworm) – largest at 3 ft, makes millions of eggs/day, shrimp in intermediate host 10. Trematodes – Fasciola hepatica a. What is the name of the organism? i. Fasciola hepatica b. What is the route of infection? i. F. hepatica —Ingestion: metacercariae from aquatic vegetation c. Signs and symptoms? i. Fasciola hepatica – symptoms coincide with episodes of bile duct obstruction and inflammation d. Prognosis? i. Chronic infection occur when flukes reside in bile duct  e. Vector? i. Reservoir in water plants, vectors are the humans, sheep and cattle that consume them f. Anything really creepy? i. Humans are the accidental definitive hosts 11. Trematodes – Schistosoma a. What is the name of the organism? i. Schistosoma – causative agent is schistosomiasis b. What is the route of infection? i. Cercariae burrow through skin of humans who contact contaminated water c. Signs and symptoms? i. Dermatitis may occur at the site where cercariae entered ii. Swimmer’s itch may develop at the site of cercariae entry d. Prognosis? i. Infections can become chronic and can be fatal when eggs calcify in tissues to become granulomas e. Vector? i. Cercariae ii. Humans are the principal definitive host f. Anything really creepy? i. 12. Nemotodes – Ascaris lumbricoides a. What is the name of the organism? i. Ascaris lumbricoides – roundworm; usually unnoticed until blocks intestines b. What is the route of infection? i. c. Signs and symptoms? i. Intestinal blockage; abdominal pain, nausea, vomiting, and intestinal obstruction if the worm burden is high d. Prognosis? i. e. Vector? i. f. Anything really creepy? i. Most common nematode infection of humans worldwide 13. Nematodes – Enterobius vermicularis a. What is the name of the organism? i. Enterobius vermicularis – pinworms, usually asymptomatic, highly infectious b. What is the route of infection? i. Female pinworms deposit their eggs in the anus c. Signs and symptoms? i. Can be asymptomatic  ii. Intense perianal itching occurs if symptomatic d. Prognosis? i. e. Vector? i. f. Anything really creepy? i. Most common parasitic worm found in the U.S. 14. Nematodes – Ancylostoma duodenale a. What is the name of the organism? i. Ancylostoma duodenale – hookworm, attaches to intestine and causes anemia b. What is the route of infection? i. Enters through feet ii. Larvae in soil burrow through skin c. Signs and symptoms? i. Anemia, lethargic behavior, and craving for peculiar foods (pica) d. Prognosis? i. e. Vector? i. Eggs hatch on ground, releasing larvae. Larvae enter through the soles of the feet and travel to the lungs. Ascend into throat to be swallowed f. Anything really creepy? i. 15. Nematodes – Trichinella spiralis (trichinellosis) a. What is the name of the organism? i. Trichinella spiralis (trichinellosis) – forms cysts in muscle tissue b. What is the route of infection? i. Encysted larvae are ingested from undercooked pork and other meats c. Signs and symptoms? i. Fever, eye swelling, gastrointestinal upset d. Prognosis? i. e. Vector? i. Digestion removes the cyst wall and the worm matures into an adult ii. Adults produce larvae in the intestines that invade tissues and form new cysts f. Anything really creepy? i.